LW Reference.bk Page 1 Monday, December 15, 2003 5:59 PM 1 LogicWorks 5 INTERACTIVE CIRCUIT DESIGN SOFTWARE REFERENCE MANUAL Capilano Computing Systems Ltd.
LW Reference.bk Page 2 Monday, December 15, 2003 5:59 PM 2 Copyright 2003 Chapter by Capilano — Computing Systems Ltd. All rights reserved. LogicWorks is a trademark of Capilano Computing Systems Ltd.
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LW Reference.
LW Reference.bk Page v Monday, December 15, 2003 5:59 PM v Using Subcircuits 49 A Simple Subcircuit Example 50 Subcircuit Primitive Type 52 Port Interface 52 Creating a Subcircuit—Top–Down 55 Creating a Subcircuit—Bottom–Up 57 4 Simulation General Information on Simulation 59 Type of Simulation 59 Simulation Memory Usage 60 Time Units 60 Signal Simulation Characteristics 61 Signal States 61 Stuck–At Levels 64 Resolution of Multiple Device Outputs 65 Resistive vs.
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LW Reference.bk Page viii Monday, December 15, 2003 5:59 PM viii Saving Frequently-Used Graphics and Pins 162 Displaying the Symbol Gallery Window 162 Hiding the Symbol Gallery Window 163 Using Elements from the Symbol Gallery 163 Adding Elements to the Symbol Gallery 163 Specifying a Symbol Gallery File 164 Creating Special-Purpose Symbols 176 Assigning a Primitive Type 176 9 Menu Reference LogicWorks File Menu Commands 177 New 177 Open 178 Close 179 Save/Save As... 179 Revert 179 Print...
LW Reference.bk Page ix Monday, December 15, 2003 5:59 PM ix Simulation Params... 205 Add to Timing 209 Add Automatically 209 Add as Group 209 Import Timing (Text)... 210 Export Timing (Text)... 211 Print Timing... 211 Print Setup... 211 LogicWorks Help Menu 211 About LogicWorks... 211 LogicWorks Online 212 Device Pop-Up Menu 212 Device Info... 212 Attributes... 212 Name... 212 Rotate and Flip Commands 213 Cut 213 Copy 213 Duplicate 213 Delete 213 Signal Pop-Up Menu 214 Signal Info... 214 Attributes...
LW Reference.bk Page x Monday, December 15, 2003 5:59 PM x Display Off 230 Normal Size 230 Enlarge 230 Reduce 230 Timing Options... 230 Timing Label Popup Menu Commands 232 Get Info...
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LW Reference.bk Page 1 Monday, December 15, 2003 5:59 PM 1 Introduction Welcome to the world of electronics design using LogicWorks! The purpose of this tutorial/manual is to get you acquainted as quickly as possible with all the powerful editing and simulation features of the program. Support on the Internet Capilano Computing operates an active World Wide Web site for LogicWorks users at www.logicworks5.com.
LW Reference.bk Page 2 Monday, December 15, 2003 5:59 PM 2 Chapter 1—Introduction be read by DesignWorks. The reverse, however, is not true due to the additional structural features in DesignWorks. Schematic Drawing Features The DevEditor module (included with LogicWorks) allows you to create libraries of custom device symbols using familiar drawing tools. Any circuit can be attached to a symbol as a subcircuit to create a simulation model.
LW Reference.bk Page 3 Monday, December 15, 2003 5:59 PM LogicWorks 5 Description 3 Simulation Features Full digital simulation capability. Circuit output may be displayed in the form of timing diagrams or on simulated output devices. Uses thirteen signal states, including forcing and resistive drive levels to correctly simulate circuits with design errors such as unconnected inputs or conflicting outputs.
LW Reference.bk Page 4 Monday, December 15, 2003 5:59 PM 4 Chapter 1—Introduction New Features in Version 4 Completely new user interface with extensive new on-screen tools and dockable windows. PLA/PROM/RAM Wizard guides you through the process of creating simulation models for these device types. Add borders and title block to circuit diagrams to create finished, professional-looking printed documentation. Paste graphics from any outside drawing program onto the LogicWorks schematic.
LW Reference.bk Page 5 Monday, December 15, 2003 5:59 PM Copyright and Trademarks 5 Copyright and Trademarks The LogicWorks software and manual are copyrighted products. The software license you have purchased entitles you to use the software on a single machine, with copies being made only for backup purposes. Any unauthorized copying of the program or documentation is subject to prosecution. The names LogicWorks and DesignWorks are trademarks of Capilano Computing Systems Ltd.
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LW Reference.bk Page 7 Monday, December 15, 2003 5:59 PM 2 Schematic Editing This chapter describes the elements of a LogicWorks circuit design and the procedures you can use to create one. Design Structure What is a Design? In LogicWorks, the term “design” refers to a complete, independent set of circuitry, including all the information needed to display, edit, and simulate it.
LW Reference.bk Page 8 Monday, December 15, 2003 5:59 PM 8 Chapter 2—Schematic Editing memory in your computer and increasing the memory allocated to the program will increase the size of the designs you can work with. A number of user-selectable parameters are stored with the design and affect the entire design when changed. These include: Attribute and pin number text style settings Display options, such as crosshairs and printed page breaks Printer page setup.
LW Reference.bk Page 9 Monday, December 15, 2003 5:59 PM Design Operations 9 connector or bus breakout which is used for schematic notation purposes. A pin is a connection point on a device. A pin is not an independent entity, since it only exists as part of a device and cannot be created or deleted separately. However, pins can have attributes, pin numbers, and other parameters that may be different from pin to pin on the same device.
LW Reference.bk Page 10 Monday, December 15, 2003 5:59 PM 10 Chapter 2—Schematic Editing Creating a New Circuit To create a new design, click on the New Document button ( ) in the toolbar, or select the New item in the File menu, then select Circuit from the list of document types. The new design will consist of an empty master circuit that will appear in a circuit window as Circuit1.CCT, Circuit2.CCT, and so on. This command does not create a disk file.
LW Reference.bk Page 11 Monday, December 15, 2003 5:59 PM The Clipboard 11 Auto-Scrolling Whenever the mouse button is depressed and moves close to the edge of a Schematic window, the window automatically scrolls to expose more area on that side. Zoom (Magnifying Glass) Tool The item in the Tool Palette is a powerful tool for moving around in a schematic diagram. Once you have activated this tool, it can be used to zoom in and out, and to control the exact area displayed on the screen.
LW Reference.bk Page 12 Monday, December 15, 2003 5:59 PM 12 Chapter 2—Schematic Editing Using Clipboard Data From Other Programs When you start up LogicWorks, the Clipboard may contain text or graphical information cut or copied from a document in another program. LogicWorks allows you to make use of this information as follows: Text information from a word processor or text editor can be pasted into a text block.
LW Reference.bk Page 13 Monday, December 15, 2003 5:59 PM Selecting Circuit Objects 13 Selecting Circuit Objects Many LogicWorks commands, such as Get Info, Cut, Copy, etc., operate on the currently selected objects. To select circuit objects, the cursor must be in the normal Point ( ) mode. Selecting a Device A single device is selected by clicking the mouse button with the pointer positioned anywhere inside the device symbol, or in any displayed attribute value associated with the symbol.
LW Reference.bk Page 14 Monday, December 15, 2003 5:59 PM 14 Chapter 2—Schematic Editing Selecting a Pin A pin is selected by clicking on the pin line close to the device. NOTE: Since an unconnected device pin is both a pin and a signal, you determine whether you get the pin or signal pop-up menu as follows: Right-clicking on the pin in the last 1/4 of the pin length away from the device will display the signal menu.
LW Reference.bk Page 15 Monday, December 15, 2003 5:59 PM Classes of Devices 15 will follow the mouse movement. Any object that intersects this rectangle when the button is released will be selected. A group of interconnected devices and signals is selected by doubleclicking on any device in the group while holding down the key. If a circuit is completely interconnected, this will select the entire circuit. The Select All command in the Edit menu selects all items in the current circuit design.
LW Reference.bk Page 16 Monday, December 15, 2003 5:59 PM 16 Chapter 2—Schematic Editing function. For example, the analog components provided in the discrete.clf library fall into this category. Subcircuit devices: These are symbols which have a simulation function defined by an internal circuit. The 7400 devices provided with LogicWorks fall into this category. The internal circuit for this kind of symbol can be viewed by double-clicking on the symbol.
LW Reference.bk Page 17 Monday, December 15, 2003 5:59 PM Placing and Editing Devices 17 See Chapter 11, Device Symbol Editing, for more information. Placing and Editing Devices Selecting a Device From a Library To select a device from a library for placement in the schematic: If necessary, use the scroll bar to scroll the library’s parts list until the desired part name is in view. Double-click on the part name in the list. Move the cursor to the current Schematic window.
LW Reference.bk Page 18 Monday, December 15, 2003 5:59 PM 18 Chapter 2—Schematic Editing After either of these operations, the cursor will be replaced by a flickering image of the selected device. This copy can be placed by clicking in the schematic, as discussed earlier. Deleting a Device Devices can be removed by either of two methods: Select the device by clicking on it (holding the key if it is a switch or other input device).
LW Reference.bk Page 19 Monday, December 15, 2003 5:59 PM 19 Drawing Signals Drawing Signals Signal lines are drawn in either Point ( mode. ) mode or Signal Drawing ( ) Interconnecting Signals If you draw a signal line so that the end of the line makes contact with a second signal line, then those two signals will be interconnected. Also, if you place a new device so that one of its pins touches an existing signal line, that pin will be connected to the signal.
LW Reference.bk Page 20 Monday, December 15, 2003 5:59 PM 20 Chapter 2—Schematic Editing Signal Line Editing Drawing from an Existing Line or a Device Pin A line can be extended from the end of an existing line or device pin using the arrow ( ) cursor. Click and hold on the end of the pin and drag away from the pin. A pair of right-angle lines will follow the cursor away from the pin as long as the mouse button is pressed. Releasing the mouse button makes these lines permanent. If the end of the line (i.
LW Reference.bk Page 21 Monday, December 15, 2003 5:59 PM 21 Drawing Signals above, the mouse button does not have to be held down while creating signals in this mode. Double-clicking terminates the signal line. Editing a Signal Line The following features are available to edit signal lines: Zap mode (entered by selecting the Zap command in the Edit menu or the Zap item in the Tool Palette) allows you to remove any single line segment from a signal connection.
LW Reference.bk Page 22 Monday, December 15, 2003 5:59 PM 22 Chapter 2—Schematic Editing Name and Pin Number Operations Names may contain any letters, numbers, or special characters that you can type on the keyboard, but are restricted in length to 15 characters. The name associated with an object can be placed anywhere on the diagram, and will be automatically removed if the object is removed. Pin numbers may contain at most 4 characters.
LW Reference.bk Page 23 Monday, December 15, 2003 5:59 PM 23 Name and Pin Number Operations Position the pencil cursor anywhere along the signal line. Click and hold the mouse button. The cursor changes to an I-beam. Still holding down the mouse button, position the cursor where you want the name to start. Release the mouse button. A blinking insertion marker appears. SYNC1| Type the desired name, up to 15 characters.
LW Reference.bk Page 24 Monday, December 15, 2003 5:59 PM 24 Chapter 2—Schematic Editing Signal names are known throughout a schematic page. Like-named signal lines are thus logically connected for simulation and netlisting purposes. Whenever a signal name is added or changed, the circuit is checked for a change in connectivity. If the name is now the same as another signal, the two signals are merged into one.
LW Reference.bk Page 25 Monday, December 15, 2003 5:59 PM Name and Pin Number Operations 25 Once Text mode is selected, the cursor changes to a pencil icon. Press and hold the mouse button with the tip of the pencil positioned inside a device symbol. As long as you hold down the mouse button an I-beam cursor will track the mouse movements. The device-name text will start at the position where you release the button. Type the desired name, and press or click the mouse button anywhere.
LW Reference.bk Page 26 Monday, December 15, 2003 5:59 PM 26 Chapter 2—Schematic Editing Adding an Invisible Name An invisible name for either a device or signal can be created in one of two ways. Use the right mouse button to select the device or signal, then select the Name command from the pop-up menu.
LW Reference.bk Page 27 Monday, December 15, 2003 5:59 PM Name and Pin Number Operations 27 determined by the vertical position of the line that was clicked on. This feature works only with signal or device names, not with pin numbers. Auto name generation—If the key is held down while a signal, device, or pin is selected, a new name is generated automatically for this item. The new name will be the same as the last one entered, except that the numeric part of the name will have been incremented.
LW Reference.bk Page 28 Monday, December 15, 2003 5:59 PM 28 Chapter 2—Schematic Editing Removing a Name A device or signal name can be removed by using the Zap pointer, as described in the section on Deleting a Device, above. If the signal has been named in multiple locations, then Zap removes the name only at the location zapped. Editing a Name The name can be changed by simply clicking the Text pointer on the signal name and editing it using the keyboard.
LW Reference.bk Page 29 Monday, December 15, 2003 5:59 PM Name and Pin Number Operations 29 Default Pin Numbers A device symbol may have default pin numbers which will appear when the device is first placed. These pin numbers are not permanent and can be edited or removed by techniques discussed in this section. These default pin numbers are assigned using the DevEditor tool. See Chapter 10, Device Symbol Editing.
LW Reference.bk Page 30 Monday, December 15, 2003 5:59 PM 30 Chapter 2—Schematic Editing Auto-Numbering Features An auto-numbering feature is provided to simplify numbering of sequential pins. If the key is held down while a pin is clicked with the Text pointer, a new number is generated automatically for this item. The new label will be the same as the last one entered, except that the numeric part of the character string will have been incremented.
LW Reference.bk Page 31 Monday, December 15, 2003 5:59 PM Text Objects 31 Creating a Text Notation If you click the text pointer on the diagram away from a device or signal line, a blinking cursor will appear at that point, and you will be able to type any desired text on the diagram. The key or the can be used to enter multiple lines in a single text block. Text entry is terminated by clicking outside of the text entry box.
LW Reference.bk Page 32 Monday, December 15, 2003 5:59 PM 32 Chapter 2—Schematic Editing The following table summarizes the options available in this dialog. Rule Between Lines Turning this switch on causes a line to be drawn after each row of characters. Draw Frame Turning this switch on causes a frame to be drawn around the text item on the schematic. Font Specs Clicking this button displays the standard Font dialog.
LW Reference.bk Page 33 Monday, December 15, 2003 5:59 PM Sheet Borders and Title Blocks 33 Pasting Graphics onto the Diagram Graphics from a number of sources can be pasted directly onto a LogicWorks schematic diagram: Windows Metafile Format (WMF) data is exported by Microsoft Word and many drawing programs, and provides a clean, compact (i.e. a minimal amount of memory is used) and scalable image (i.e. prints cleanly on various types of printers).
LW Reference.bk Page 34 Monday, December 15, 2003 5:59 PM 34 Chapter 2—Schematic Editing Click on it once to select it (if the object has been previously set to be a background item, you will have to hold the order to select it. and keys in Select the Get Info command in the Options menu. Select the Draw Frame item to draw a border around the graphic. Select the Make Background item to prevent the item from being selected by a normal mouse click.
LW Reference.bk Page 35 Monday, December 15, 2003 5:59 PM 3 Advanced Schematic Editing This chapter provides information on the more advanced schematic editing features of LogicWorks. Bussing The bussing facility allows any combination of named signals to be represented by a single line and any subset of these to be brought out through a “breakout” at any point along the bus line. Properties of Busses A bus is treated by LogicWorks as a signal with special properties.
LW Reference.bk Page 36 Monday, December 15, 2003 5:59 PM 36 Chapter 3—Advanced Schematic Editing If you select a bus line, then pull down the Schematic menu and select the Get Info command. The displayed info box will show a list of the signals currently contained in the bus. A given signal can be present only in one bus. If you attempt to connect together two signals in different busses, a warning box will be displayed and the connection will be canceled.
LW Reference.bk Page 37 Monday, December 15, 2003 5:59 PM Bussing 37 Once such a breakout has been added to the bus, all signals in all attached breakouts are considered part of that bus.
LW Reference.bk Page 38 Monday, December 15, 2003 5:59 PM 38 Chapter 3—Advanced Schematic Editing Bus Operations Creating a Bus A bus can be created by any one of the following methods: Select the Draw Bus tool ( ) in the Tool Palette. Draw any desired contiguous set of lines on the diagram using the usual signal drawing techniques. This bus will have no internal signals initially. Signals will be added implicitly when it is connected to any breakout or bus pin.
LW Reference.bk Page 39 Monday, December 15, 2003 5:59 PM 39 Bussing Then select the New Breakout command. The following dialog box will appear: If a bus or breakout was selected on the circuit diagram, the New Breakout Info dialog will display a list of the signals in that bus or breakout; otherwise, it will be empty. If this list already matches the signals you want in the new breakout, then just click the “OK” button or press on the keyboard.
LW Reference.bk Page 40 Monday, December 15, 2003 5:59 PM 40 Chapter 3—Advanced Schematic Editing Note that the “..” format implies that bussed signal names cannot contain periods. The signals specified will always appear in the order given in this list from top to bottom in standard orientation. Specifying numbered signals from lowest numbered to highest is a good practice, as in the first example above, since this matches the standard library symbols.
LW Reference.bk Page 41 Monday, December 15, 2003 5:59 PM Bussing 41 Press the key. The breakout pin and the attached signal will be renamed as entered. IMPORTANT: The notation on the breakout pin is always the same as the name of the attached signal. Changing the breakout pin renames the attached signal and will detach it from any like–named signals already in the bus.
LW Reference.bk Page 42 Monday, December 15, 2003 5:59 PM 42 Chapter 3—Advanced Schematic Editing For more information on creating device symbols with bus pins, see Chapter 10, Device Symbol Editing. Power and Ground Connections LogicWorks uses a type of pseudo–device symbol called a “Signal Connector Device” to maintain connectivity between like–named power and ground symbols that are used on circuit diagrams.
LW Reference.bk Page 43 Monday, December 15, 2003 5:59 PM Connectors and Discretes IMPORTANT: 43 The signal attached to a signal connector device is actually named to match the pin name of the signal connector pin specified in device symbol editor, not the type name. In most of the power and ground symbols provided with LogicWorks, these two names are the same. However, it is possible to create a symbol called “Ground” (for example) in a library that actually names the attached signal “GND”.
LW Reference.bk Page 44 Monday, December 15, 2003 5:59 PM 44 Chapter 3—Advanced Schematic Editing Separate Devices NOTE: Single Device When the single–pin devices are used, every device must carry exactly the same name, although the names can be invisible if desired. Handling Discrete Components Discrete components—such as capacitors, transistors, etc.—can be handled just like any other device, except for the following special considerations.
LW Reference.bk Page 45 Monday, December 15, 2003 5:59 PM Using Attributes 45 Using Attributes LogicWorks allows arbitrary blocks of text to be associated with any device, signal, or pin in a design, or with the design itself. The blocks of text are called attributes. Attributes have a wide variety of uses, including: Displaying device name, component value, etc. Storing data for use by external systems such as simulators, PCB layout, analysis tools, etc.
LW Reference.bk Page 46 Monday, December 15, 2003 5:59 PM 46 Chapter 3—Advanced Schematic Editing Predefined Attribute Fields The following table describes the fixed list of attribute fields provided in each LogicWorks design. Attribute fields cannot be added or deleted in LogicWorks. Field Name Used In Description CctName Design Design file name. Sets the window title and name of next saved file. Delay.Dev Device Specifies device delay. For most devices, a single decimal integer 0 to 32,767.
LW Reference.bk Page 47 Monday, December 15, 2003 5:59 PM Using Attributes 47 Editing Attribute Data (General) The following dialog box is used to enter or edit attribute data: NOTE: The same Attributes Dialog is used to enter data for all object types. This section discusses the general operation of this dialog. The following sections will discuss each object type. Basic Procedure To edit the contents of a field, simply select the field name in the list.
LW Reference.bk Page 48 Monday, December 15, 2003 5:59 PM 48 Chapter 3—Advanced Schematic Editing Editing Device Attribute Data The Attributes Dialog can be entered in one of two ways: Click on the device to select it, then select the Get Info command from the Schematic menu, then click on the Attributes... button. Or: Display the device’s pop–up menu (right–click on the device). Then select the Attributes command from the menu. The standard Attributes Dialog will appear.
LW Reference.bk Page 49 Monday, December 15, 2003 5:59 PM Using Subcircuits 49 From the pop–up menu, select the Rotate Right or Rotate Left command. Setting Attribute Text Style Attribute text style is set globally for the entire design. There is no way to set text style for an individual item. IMPORTANT: Changing the attribute text style affects all visible attributes throughout the design. LogicWorks may alter text alignment and position to accommodate a new text size.
LW Reference.bk Page 50 Monday, December 15, 2003 5:59 PM 50 Chapter 3—Advanced Schematic Editing Following is a short summary of the rules governing subcircuit devices. More information on each of these topics is included in the following sections. The “pins” on the subcircuit device symbol represent connections to specific input–output points on the internal circuit. A “port connector” pseudo–device must be placed in the subcircuit corresponding to each pin on the parent symbol.
LW Reference.bk Page 51 Monday, December 15, 2003 5:59 PM Using Subcircuits 51 Note that it contains two symbols, both representing subcircuit devices. Both symbols are of the same type, RSFF, and therefore share the same internal circuit definition. The two devices are named FF1 and FF2. Opening either one of these devices reveals the following internal circuit: This circuit consists of three device symbols, G1, G2, and G3, representing physical devices, and a number of port connector symbols.
LW Reference.bk Page 52 Monday, December 15, 2003 5:59 PM 52 Chapter 3—Advanced Schematic Editing The signal RESET/ does not connect to a port connector, so it represents a separate signal in the internal circuit. Like the devices G1, etc., each signal in RSFF actually represents two physical signals. Subcircuit Primitive Type Subcircuit device symbols are simply device symbols which have the primitive type “SUBCCT.” Device symbols with any other primitive type cannot be used as subcircuit devices.
LW Reference.bk Page 53 Monday, December 15, 2003 5:59 PM 53 Using Subcircuits The port interface is rechecked whenever any change is made. Thus, as soon as a port connector is added or removed, or its name is changed, the port interface will be updated to reflect the new logical connections. However, to avoid excessive warning messages, error checking is performed only when an internal circuit is opened or closed. A warning box will be displayed if any error is found. This checking cannot be disabled.
LW Reference.bk Page 54 Monday, December 15, 2003 5:59 PM 54 Chapter 3—Advanced Schematic Editing IMPORTANT: If you create a port connector symbol using the device symbol editor, the pin type (input, output or bidirectional) must be set carefully for each pin on the port connector. The pin on the Port Connector symbol must be of the opposite type to the corresponding pin on the parent device symbol. For example, a signal coming in to the subcircuit is actually an output from the port connector pin.
LW Reference.bk Page 55 Monday, December 15, 2003 5:59 PM 55 Using Subcircuits Pin List (in symbol editor) Subcircuit Block Symbol The corresponding Bus Port Connector to be used inside this device would look as follows: Pin List (in symbol editor) Port Connector Symbol The comments above in the section, Port Pin Type, apply to each internal pin in a bus pin. Remember that the name of the bus pin in the port connector is not significant.
LW Reference.bk Page 56 Monday, December 15, 2003 5:59 PM 56 Chapter 3—Advanced Schematic Editing to be used because the default primitive type for a symbol is SUBCCT.) Save the symbol in a library. Use the symbol as desired in your schematic. Use the New Design command to create a new and completely independent design. Create the schematic for the subcircuit in this design. You may use any existing parts from libraries except the parent symbol that we created above.
LW Reference.bk Page 57 Monday, December 15, 2003 5:59 PM Using Subcircuits 57 designs, then click the Attach button. The selected design will now be brought to the front. Close its window. If the Update/Revert/Cancel option box appears, select Update. The subcircuit is now attached to the parent symbol and has ceased to exist as an independent design. Creating a Subcircuit—Bottom–Up In a bottom–up design process, we create the subcircuit first then use it to define the pins on the parent symbol.
LW Reference.bk Page 58 Monday, December 15, 2003 5:59 PM 58 Chapter 3—Advanced Schematic Editing the Pin List must have a corresponding graphical pin on the device symbol. Save the symbol to the library. It will be saved with a copy of the selected internal circuit; that is, you can close or discard the internal circuit window, as the circuit is now saved in the library. The new subcircuit device may be selected from the library and placed in any schematic as desired.
LW Reference.bk Page 59 Monday, December 15, 2003 5:59 PM 4 Simulation This chapter provides more detailed information on LogicWorks’ simulation capabilities. General Information on Simulation LogicWorks has the ability to perform a realistic simulation of any digital circuit. Obviously, though, any simulation of any system must be limited in detail and must make certain assumptions.
LW Reference.bk Page 60 Monday, December 15, 2003 5:59 PM 60 Chapter 4—Simulation The simulation is “event–driven,” where an event is a change in the level of a signal. Each time an event occurs, a list is made of all the devices whose inputs are affected by that event. Any other events occurring at the same time are similarly evaluated, and affected devices added to the list.
LW Reference.bk Page 61 Monday, December 15, 2003 5:59 PM Signal Simulation Characteristics 61 Signal Simulation Characteristics Signal States LogicWorks uses 13 different device output states in order to track conditions within your circuit. These states can be broken into three groups, as follows: Forcing States (denoted by suffix .F): LOW.F HIGH.F DONT01.F DONT0Z.F DONT1Z.F CONF.F Resistive States (denoted by suffix .R): LOW.R HIGH.R DONT01.R DONT0Z.R DONT1Z.R CONF.
LW Reference.bk Page 62 Monday, December 15, 2003 5:59 PM 62 Chapter 4—Simulation Description of States The High and Low states are the normal ones expected in a binary circuit, but are not sufficient to realistically simulate circuit operation, so the High Impedance, Don’t Know and Conflict states are added. There will always be some cases where the simulation will not correctly mimic what would appear in a real circuit, and some of these cases are discussed in following sections.
LW Reference.bk Page 63 Monday, December 15, 2003 5:59 PM Signal Simulation Characteristics 63 For the purposes of simulation, all circuits must have some provision for initialization to a known state. In most cases, circuits can be initialized by using the Clear Unknowns command or by setting the initial value attribute, described in “Setting Initial Values” on page 75.
LW Reference.bk Page 64 Monday, December 15, 2003 5:59 PM 64 Chapter 4—Simulation produce a DONT0Z output, which resolves correctly to a LOW on the output—regardless of the state of IN1—using the rules described previously. Conflict The Conflict state (“C” on a logic probe) results when two device outputs are connected and are of different or unknown states—taking into account the rules described previously. State Display The Timing window displays the various signal states in different colors.
LW Reference.bk Page 65 Monday, December 15, 2003 5:59 PM Signal Simulation Characteristics 65 Using the Stick High or Stick Low buttons in the Stick Signals command. Each of these methods is described in more detail in the relevant section of this manual. Clearing Stuck Levels The stuck status can only be cleared by one of the following user actions: Typing the spacebar while viewing the signal using the signal probe tool; or Clearing the “stuck” switch in the Stick Signals command.
LW Reference.bk Page 66 Monday, December 15, 2003 5:59 PM 66 Chapter 4—Simulation Resistive vs. Forcing Drive All primitive devices in LogicWorks output a forcing drive level, except for the Resistor primitive device. The function of the Resistor device is to convert a forcing drive on one side into a resistive drive on the other. This can be used to modify the output of any existing device type by placing a resistor in series with it.
LW Reference.bk Page 67 Monday, December 15, 2003 5:59 PM Signal Simulation Characteristics 67 Probing a Pin If the probe tip is clicked on a device pin close to the device body, the probe shows the driving level of that pin, rather than the state of the attached signal.
LW Reference.bk Page 68 Monday, December 15, 2003 5:59 PM 68 Chapter 4—Simulation driving the line. If a non–stuck value is forced, the signal value will revert to its appropriate new level when any change occurs on a device output driving the line. The spacebar “unstick” command causes the signal to revert to its driven value. See also the Stick Signals command in Chapter 12, Menu Reference, for more information on stuck values.
LW Reference.bk Page 69 Monday, December 15, 2003 5:59 PM Device Simulation Characteristics 69 Device Simulation Characteristics Device and Pin Delay This section describes how to set delay values for primitive devices, subcircuit devices, and pins. Primitive Device Delay Primitive devices (e.g., those with a program–defined simulation model) have a single delay value which can be set to any integer value from 0 to 32,767. This delay is applied when any input change causes any output change.
LW Reference.bk Page 70 Monday, December 15, 2003 5:59 PM 70 Chapter 4—Simulation A pin delay acts like a “buffer” device with the given delay inserted inline with the pin. On an input pin, the device simulation model will not see a change in signal value until after the pin delay has elapsed. On an output pin, the pin delay is added to the overall device delay for any changes scheduled on that pin. Setting the Delay To set the delay for a device, first select the device by clicking on it.
LW Reference.bk Page 71 Monday, December 15, 2003 5:59 PM Device Simulation Characteristics 71 time will never advance. This will stop the Timing window from updating until some delay is inserted in the loop. Where Delays are Stored For devices, the delay attribute field is called “Delay.Dev”; for pins, it is “Delay.Pin”. An empty or invalid string will be interpreted as the default value, usually 1 for devices and 0 for pins.
LW Reference.bk Page 72 Monday, December 15, 2003 5:59 PM 72 Chapter 4—Simulation Input Signal Values For all device types except switches, the signal values High Impedance and Conflict are treated as Don’t Know when applied to a device input. When a device is first created, all input signals take the High Impedance state, and outputs are set depending on their type—normally to the Don’t Know state. Thus an unused input pin will appear as an unknown input to a device, which may affect its output level.
LW Reference.bk Page 73 Monday, December 15, 2003 5:59 PM Device Simulation Characteristics 73 primitive types as well as subcircuit devices. The following table summarizes the level mappings that occur. NOTE: External Signal Value Internal Signal Value LOW.H HIGH.H LOW.L HIGH.L HIGH.H LOW.H HIGH.L LOW.L All others Unchanged 1) The logical inversion of the pin is completely independent of the graphical representation of the pin.
LW Reference.bk Page 74 Monday, December 15, 2003 5:59 PM 74 Chapter 4—Simulation Simulation Clearing and Initialization The LogicWorks simulator provides a number of mechanisms to assist in setting initial values and resetting a simulation. The Clear Simulation Operation You can invoke the Clear Simulation operation by clicking on the Reset button ( in the Simulator toolbar. This operation performs the following steps: Other tools (such as Timing) are notified and perform their own processing.
LW Reference.bk Page 75 Monday, December 15, 2003 5:59 PM 75 Simulation Clearing and Initialization Any primitive type with storage capability (such as flip–flop, register, or counter) that has a Don’t Know output value is cleared, either to its specified initial value (if any) or to zero. A single device that currently has an unknown output state is randomly selected and queued for re-evaluation. A special input mapping is done so that all unknown inputs are treated as zero.
LW Reference.bk Page 76 Monday, December 15, 2003 5:59 PM 76 Chapter 4—Simulation NOTE: 1) It is left completely to the user to decide if the specified initial values make sense. No checking is done to determine if a given device output value is the reasonable result of the device’s current input. NOTE: 2) Devices do not have initial value settings, since their values are completely determined by the state of their output pins. See the section, Pin Initial Values, below.
LW Reference.bk Page 77 Monday, December 15, 2003 5:59 PM Schematic Simulation Issues 77 See also Chapter 6, Advanced Schematic Editing Editing an Open Internal Circuit A number of issues arise if you have used the same subcircuit device type multiple times in a design and you open one copy for editing (i.e., by using the Push Into command or by double–clicking on the device).
LW Reference.bk Page 78 Monday, December 15, 2003 5:59 PM 78 Chapter 4—Simulation The Port Interface The connection between a pin on a parent device symbol and the corresponding signal in the internal circuit is quite complex, from a simulation standpoint. In order for this connection to act like a “hard wire” between the two levels, the following conditions must be met: The pin type on the parent device symbol must be “bidirectional.
LW Reference.bk Page 79 Monday, December 15, 2003 5:59 PM 79 Schematic Simulation Issues NOTE: Pin Type Effect Input This will prevent that pin from ever driving the attached signal, regardless of drives in the internal circuit. Output / Three–state This will pass the sum of the internal drives up to the parent pin without any translation. Signal value changes on the signal attached to the parent pin will not be passed to the internal circuit.
LW Reference.bk Page 80 Monday, December 15, 2003 5:59 PM 80 Chapter 4—Simulation Pin Delays and Inversion The normal pin delay and inversion settings can be applied to the port interface. A non–null value in the Invert.Pin attribute field will cause any signal values passing in either direction to be inverted. An integer value in the Delay.Pin attribute will cause the specified delay to be inserted inline with level changes passing in either direction.
LW Reference.bk Page 81 Monday, December 15, 2003 5:59 PM Simulation Models 81 Special Signal Names 0 and 1 The signal names 0 and 1 are recognized by the simulator as special. If any signal is named 0, it will be given a Stuck Low value. If a signal named 1 is found, it will be given a Stuck High value. These values can be cleared or changed using the signal probe, if desired. See the Signal Probe command in Chapter 12, Menu Reference, for more information.
LW Reference.bk Page 82 Monday, December 15, 2003 5:59 PM 82 Chapter 4—Simulation Primitive Devices on the Schematic The primitive devices provided in the primlogi.clf and primgate.clf libraries can be used at any time as part of a schematic, whether or not the simulator is installed. However, these libraries are not intended to match any real logic families and do not have any part name or pin number information associated with them.
LW Reference.bk Page 83 Monday, December 15, 2003 5:59 PM 5 The Timing and Simulator Tools The Timing Window The Timing window allows you to display timing waveforms in graphical form and updates continuously and automatically as the simulation progresses. Only one Timing window can be displayed and it displays information for the active design. If multiple sub-circuit levels are open, all displayed waveforms are shown in a single window.
LW Reference.bk Page 84 Monday, December 15, 2003 5:59 PM 84 Chapter 5—The Timing and Simulator Tools Here are the components of the Timing window: Time Scale Area Located just below the Timing window’s title bar, the time scale is used to establish the absolute timing of value changes in the trace area. The scale is dependent upon the timing resolution (set using the < and > buttons in the Simulator Palette).
LW Reference.bk Page 85 Monday, December 15, 2003 5:59 PM Displaying Signals in the Timing Window 85 Select the traces to be removed by clicking in the label area of the timing window. You can remove multiple traces in one operation by holding the key to select multiple labels. Windows—Right–click on the selected name in the label area at the left side of the Timing window, then select the Remove command in the pop-up menu.
LW Reference.bk Page 86 Monday, December 15, 2003 5:59 PM 86 Chapter 5—The Timing and Simulator Tools Order Within a Group For the purposes of displaying a hexadecimal value for a group, the order of signals within the group is important. When a group is created, the following rules are used to establish the order: If the signal name has a numeric part (e.g., D12 or WRDAT4X), then the numeric part is used to sort the signals.
LW Reference.bk Page 87 Monday, December 15, 2003 5:59 PM 87 The Simulator Toolbar The Simulator Toolbar Show/Hide Timing Window Add Signal to Timing Triggers Simulation Params Stick Signals Reset Simulation Clear Unknowns Zoom In Zoom Out Normal Zoom Current Time Speed Control Stop Single Step Run Displaying and Hiding the Simulator Toolbar The Simulator toolbar is displayed by default when the Timing window is shown. You may move it or close it.
LW Reference.bk Page 88 Monday, December 15, 2003 5:59 PM 88 Chapter 5—The Timing and Simulator Tools Simulator Toolbar Controls The buttons in the Simulator toolbar control the simulator as follows: Reset Clears all pending events, sets time to zero and recalculates all device states. Run Causes the simulator to execute at the fastest possible speed. Step Causes the simulator to execute one time step. < (Zoom In) Increases horizontal display resolution in the Timing window, i.e.
LW Reference.bk Page 89 Monday, December 15, 2003 5:59 PM 89 The Simulator Toolbar Signal Value Condition Controls The controls related to the signal condition are summarized in the following table: Names In this text box, you can type the names of one or more signals whose values will be compared to the hexadecimal integer value typed in the Value box. One or more signals can be entered using the following formats: CLK D7..
LW Reference.bk Page 90 Monday, December 15, 2003 5:59 PM 90 Chapter 5—The Timing and Simulator Tools Stop Stops the simulator immediately. Reference Line Draws a reference line at this time on the Timing waveform display. Timing Window Editing Right-clicking in the trace area of the Timing window will dispaly a pop-up menu. It provides the following commands: Copy, Paste,and Select All (selects all traces). NOTE: Timing traces can only be editing in the future—i.e.
LW Reference.bk Page 91 Monday, December 15, 2003 5:59 PM Timing Window Editing 91 To set the selection interval, click and hold down the mouse button in the time scale at either end of the desired interval. Drag left or right until the desired interval is enclosed. When the mouse button is released, the select interval is set, and two selection interval lines will appear. If any of the signal labels were selected, the timing signal within the selected interval will be highlighted in the Timing window.
LW Reference.bk Page 92 Monday, December 15, 2003 5:59 PM 92 Chapter 5—The Timing and Simulator Tools NOTE: The selection operations in the Timing window have no effect on selections in the Schematic window. Selecting All Traces or All Time To select a specific time interval in all traces on the diagram: Use the Select All command in the Edit menu to select the entire diagram. Drag–select an interval in the time scale area without clicking in the trace area.
LW Reference.bk Page 93 Monday, December 15, 2003 5:59 PM Timing Window Editing 93 Deselecting Clicking anywhere in the trace area that is not in a trace will deselect the labels and selection interval. Clicking in the label area above or below the label list deselects all traces but leaves the current interval selected. Summary of Timing Edit Commands The following table summarizes operation of the Timing edit commands in the Edit menu.
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LW Reference.bk Page 95 Monday, December 15, 2003 5:59 PM 6 Primitive Devices Every device on a LogicWorks schematic has a characteristic known as its primitive type. The primitive type is set when the part entry in the library is created, and cannot be changed for individual devices on the schematic.
LW Reference.bk Page 96 Monday, December 15, 2003 5:59 PM 96 Chapter 6—Primitive Devices Schematic and Pseudo–Device Primitive Types A small number of primitive types are used to distinguish the types of symbols used strictly for schematic diagramming purposes. These symbol types have no inherent simulation properties. IMPORTANT: The pseudo–device types have specific pin order requirements that must be followed if you create one of these symbols using the DevEditor tool.
LW Reference.bk Page 97 Monday, December 15, 2003 5:59 PM Simulation Primitive Types 97 Simulation Primitive Types In LogicWorks primitive device types, the function of each pin is determined by its type (i.e., input or output) and by its sequential position in the device’s Pin List (as seen when the part is opened in the DevEditor). Pin name is not significant. Each type has specific rules about the ordering of pins. Failure to adhere to these rules will result in incorrect simulator operation.
LW Reference.bk Page 98 Monday, December 15, 2003 5:59 PM 98 Chapter 6—Primitive Devices The following table lists the available primitives and their functions. Primitive Type Description Related Type Max.
LW Reference.bk Page 99 Monday, December 15, 2003 5:59 PM 99 Simulation Primitive Types Primitive Type Description Related Type Max.
LW Reference.bk Page 100 Monday, December 15, 2003 5:59 PM 100 Chapter 6—Primitive Devices Pin Inversion In addition to the pin function options described in this chapter, any pin on any device can be inverted by specifying a value in the Invert.Pin attribute field. Any non–empty value will cause the pin logic to be inverted. See Chapter 7, Simulation, for more information Gates and Buffers The primgate.clf library contains the primitive gates that have a built–in simulation function.
LW Reference.bk Page 101 Monday, December 15, 2003 5:59 PM 101 Gates and Buffers Gate Definition The gate types, except NOT, can be created with any number of inputs from 0 to 799. They are defined as shown in the following table. Function Output is... Output is DONT if...
LW Reference.bk Page 102 Monday, December 15, 2003 5:59 PM 102 Chapter 6—Primitive Devices Pin Inversions The logic of any pin on any device can be inverted by placing a non–empty value in the Invert.Pin attribute field of the pin. For example, to create the following AND gate with one inverted pin: ...the following steps must be taken in the DevEditor tool: Create the desired graphic symbol using the DevEditor’s drawing tools. Place the three pins as shown.
LW Reference.bk Page 103 Monday, December 15, 2003 5:59 PM Gates and Buffers 103 Close the PartType Configuration dialog and save the part to a library in the usual manner. NOTE: 1) The logical inversion of the pin is completely independent of the graphical representation of the pin. That is, using the “inverted pin” graphic in the DevEditor does not invert the pin logic in the simulator. You must set the Invert.Pin field to invert the logic.
LW Reference.bk Page 104 Monday, December 15, 2003 5:59 PM 104 Chapter 6—Primitive Devices Three–State Buffer The three–state buffer has N data inputs, N data outputs, and an optional active–low enable input. If the enable input exists and is high, all outputs enter a High Impedance state. If the enable input doesn’t exist or is low, each output will follow the corresponding input if it is low or high, or produce a Don’t Know level otherwise. NOTE: N is a placeholder.
LW Reference.bk Page 105 Monday, December 15, 2003 5:59 PM Gates and Buffers 105 Making Non–Inverting Buffers The Buffer primitive type can also be used to make a non–inverting buffer—that is, a buffer with its outputs always enabled—simply by omitting the enable input. This can be used for the following purposes: To represent a non–inverting buffer or level translator in a design. To insert a delay in a signal path without affecting the logic of the signal.
LW Reference.bk Page 106 Monday, December 15, 2003 5:59 PM 106 Chapter 6—Primitive Devices Logic Devices Multiplexer This is a device that selects one of N data inputs and routes it to a corresponding output line. There can from 1 to 256 outputs, plus an optional enable input, as long as the total pin count does not exceed the 800–pin limit.
LW Reference.bk Page 107 Monday, December 15, 2003 5:59 PM 107 Logic Devices Multiplexer Pin Variations A number of variations in multiplexer logic are possible with this primitive type, depending on which input and output pins are included. The following table summarizes the possible variations. Samples are shown with M=1 and N=2, but any combination of M and N can be used within the maximum pin limit of 800.
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LW Reference.bk Page 109 Monday, December 15, 2003 5:59 PM 109 Logic Devices Adder/Incrementer The N–bit Adder accepts one or two N–bit input arguments and (optionally) a 1–bit carry, and outputs their N–bit sum plus an optional 1–bit carry out. Multiple Adders can be connected together by feeding the Carry Out from each stage to the Carry In of the next more significant stage. The Carry In to the least significant stage should be set to zero.
LW Reference.bk Page 110 Monday, December 15, 2003 5:59 PM 110 Chapter 6—Primitive Devices Subtractor/Decrementer The Subtractor primitive type behaves identically to the Adder type except that a subtract or decrement operation is performed, depending upon pin configuration.
LW Reference.bk Page 111 Monday, December 15, 2003 5:59 PM Logic Devices 111 Flip–Flop Initialization Note that when a flip–flop is first placed in the schematic, it is in an unknown state and must be correctly initialized before it will produce predictable outputs. This can be done in the following ways: Adding circuitry to force an explicit reset. Using the Clear Unknowns button or menu command to force an initial state before starting the simulation.
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LW Reference.bk Page 113 Monday, December 15, 2003 5:59 PM Logic Devices 113 The following table illustrates some pin variations available for the Register primitive type: 4–bit register with active–high clear 4–bit register with active–low clear (using pin inversion) 4–bit register without clear Counter This device implements an N–bit, presettable, synchronous, positive-edge– triggered, up/down counter with active–low enable.
LW Reference.bk Page 114 Monday, December 15, 2003 5:59 PM 114 Chapter 6—Primitive Devices Cascading Multiple Counters Counter primitives with the optional Enable and Carry Out pins can be cascaded to form larger synchronous counters as follows: Counter Pin Variations The following table summarizes the possible pin usage variations for the counter primitive type. The samples are shown with N=4, although the number of bits can be anywhere in the range 1 to 256.
LW Reference.bk Page 115 Monday, December 15, 2003 5:59 PM 115 Logic Devices Optional Inputs Including Load Inputs Excluding Load Inputs CLR, UP/DN, ENABLE CLR, UP/DN CLR none NOTE: CO can be independently included or omitted in any of the above variations.
LW Reference.bk Page 116 Monday, December 15, 2003 5:59 PM 116 Chapter 6—Primitive Devices Shift Register The shift register is an N–bit, positive-edge–triggered device with serial or optional parallel load. When the Shift/Load input is low, data from the N parallel data input lines is transferred to the outputs on the rising edge of the next clock.
LW Reference.bk Page 117 Monday, December 15, 2003 5:59 PM 117 Logic Devices Creating Synchronized or Offset Clocks When the Clear Simulation operation is selected (via the Reset button on the Simulator Palette), all clocks in the design are restarted. Clock outputs will be set to the low state and the timer for the low period will be restarted. Clock high and low times, combined with pin inversion and pin delay settings, can be used to precisely determine the relationship between two clock outputs.
LW Reference.bk Page 118 Monday, December 15, 2003 5:59 PM 118 Chapter 6—Primitive Devices One Shot The One Shot is used to generate an output pulse of a fixed length when it is triggered by the rising edge of the trigger input. Two parameters can be set for a One Shot: the delay from the rising edge of the input to the start of the output pulse, and the duration of the pulse.
LW Reference.bk Page 119 Monday, December 15, 2003 5:59 PM I/O Simulation Pseudo–Devices 119 SPST Switch The SPST switch device simulates the actions of a simple open/closed switch in a digital circuit. When a switch is first created, it is open, and both connections present a high impedance logic level. Clicking on the switch (between the two dots) with the cursor in Point mode causes the switch arm to close and the switch to “conduct.
LW Reference.bk Page 120 Monday, December 15, 2003 5:59 PM 120 Chapter 6—Primitive Devices Hex Keyboard The hex keyboard outputs the binary equivalent of a hexadecimal digit on four binary lines. A “key” is pressed by positioning the tip of the arrow cursor in the desired key number and clicking the mouse button. The binary data on the output lines will change to reflect the new value and will remain set until the next key is pressed.
LW Reference.bk Page 121 Monday, December 15, 2003 5:59 PM 7 RAMs and Programmable Devices This chapter provides details on creating and using RAM (Random Access Memory), PROM (Programmable Read-Only Memory) and PLA (Programmable Logic Array) devices with user-specified data. These devices are created using the PROM/RAM/PLA Wizard. Apart from this slight difference in terminology, procedures are essentially the same on both systems. These terms will be used interchangeably in the rest of this chapter.
LW Reference.bk Page 122 Monday, December 15, 2003 5:59 PM 122 Chapter 7—RAMs and Programmable Devices RAM Device Characteristics The RAM primitive device supports the direct simulation of static Random Access Memory devices in a variety of configurations. You can create custom RAM devices with a variety of pin options. This table summarizes the options available in the RAM primitive type. Chip Enables 0, 1, 2, or 3 active–low chip enables.
LW Reference.bk Page 123 Monday, December 15, 2003 5:59 PM The RAM, PROM and PLA Primitive Types 123 RAM Pin Delay and Inversion Options The normal options for pin delay (using the Delay.Pin attribute field) and pin inversion (using the Invert.Pin attribute field) can be used with RAM devices. RAM Device Limitations RAM devices must fall within all of the following limits: NOTE: 30 address-line inputs. 256 bits per word. Total memory space < 231 bytes.
LW Reference.bk Page 124 Monday, December 15, 2003 5:59 PM 124 Chapter 7—RAMs and Programmable Devices Total PROM memory space < 231 bytes. Sufficient program memory free to allocate a block twice the size of the simulated memory space. PLA Device Characteristics In LogicWorks, a PLA (Programmable Logic Array) models a group of AND gates feeding into a single OR (active high) or NOR (active low) gate for each output bit.
LW Reference.bk Page 125 Monday, December 15, 2003 5:59 PM Using the PROM/RAM/PLA Wizard 125 PLA primitive type—for example, a PAL10L8-type device. However, most PLDs are simulated by creating a subcircuit containing one or more PLA primitive devices, plus the other required logic and wiring.
LW Reference.bk Page 126 Monday, December 15, 2003 5:59 PM 126 Chapter 7—RAMs and Programmable Devices Enter the desired number of inputs and outputs and select the appropriate options. For more information on these options, see “RAM Device Characteristics” on page 122. Click the Next button when done. Enter the name that you wish the new part to be saved under and select the destination library. If you need to create a new library, click the New Lib button.
LW Reference.bk Page 127 Monday, December 15, 2003 5:59 PM 127 Using the PROM/RAM/PLA Wizard Creating a PROM Device from a Data File This section describes the steps necessary to create a PROM device and read its contents from a data file. Two file formats are supported: Intel hex format—This is a structured format generated by many assemblers and development systems. This format is more reliable because it includes a checksum, but is not practical to generate by hand.
LW Reference.bk Page 128 Monday, December 15, 2003 5:59 PM 128 Chapter 7—RAMs and Programmable Devices Enter the desired number of inputs and outputs and select the “Intelformat hex” or “raw hex” data-entry method, as appropriate. Click the Next button. Click the “Select Intel Hex File” or “Select Raw Hex File” button and locate the desired input file. The Format Help button can be used to bring up a description of the selected format. Click the “Next” button.
LW Reference.bk Page 129 Monday, December 15, 2003 5:59 PM Using the PROM/RAM/PLA Wizard 129 Each string of hexadecimal characters (0–9, a–f, A–F) specifies one word in the array. Words are entered starting with address 0, then address 1, and so on. Any non-hexadecimal character (including blanks, non-hex letters, punctuation and line breaks) separates one word from the next. Each hex character represents 4 bits, with the rightmost character representing the least significant bits in the word (i.
LW Reference.bk Page 130 Monday, December 15, 2003 5:59 PM 130 Chapter 7—RAMs and Programmable Devices Enter the hex data in the text box provided, using the format described earlier. The Format Help button can be used to bring up a description of the format along with some examples. Click the “Next” button. Enter the name that you wish the new part to be saved under and select the destination library. If you need to create a new library, click the New Lib button.
LW Reference.bk Page 131 Monday, December 15, 2003 5:59 PM Using the PROM/RAM/PLA Wizard 131 Select the PLA device type and click the Next button: Enter the desired number of inputs and outputs and select the “Read data from a DWL-format PLA file” data-entry method. Click the Next button. Click the “Select DWL File” button and locate the desired input file. The Format Help button can be used to bring up a description of the DWL format. Click the “Next” button.
LW Reference.bk Page 132 Monday, December 15, 2003 5:59 PM 132 Chapter 7—RAMs and Programmable Devices Creating a PLA Device with Manual Data Entry This section describes the steps necessary to create a PLA device and directly enter the data that will be stored in it: Here is a summary of the format used to enter PLA data: Each PLA output is specified separately. The Wizard will step you through the outputs one page at a time, starting with the least significant output bit.
LW Reference.bk Page 133 Monday, December 15, 2003 5:59 PM Editing RAM, PROM, and PLA Devices 133 Enter the desired number of inputs and outputs and select the “Enter product term data manually” data entry method. Click the Next button. For each output, enter the term data in the text box provided, using the format described earlier. The Format Help button can be used to bring up a description of the format along with some examples. Click the “Next” button.
LW Reference.bk Page 134 Monday, December 15, 2003 5:59 PM 134 Chapter 7—RAMs and Programmable Devices IMPORTANT: The RAM, PROM, or PLA device definition contains structure information that cannot be edited after the device is created. Adding or deleting any pins using the device symbol editor will invalidate the device definition and render it useless. The device symbol editor can be used to make the following changes to a RAM, PROM, or PLA device, if desired: Any graphical changes to the symbol.
LW Reference.bk Page 135 Monday, December 15, 2003 5:59 PM 8 Device Symbol Editing Device symbols are an important resource in your design creation process. Whether you primarily use the symbols provided with LogicWorks, or you create special libraries for your own use, the completeness and accuracy of this data has a major effect on your design flow. Library files generally outlast any one design and are used for many years across many projects.
LW Reference.bk Page 136 Monday, December 15, 2003 5:59 PM 136 Chapter 8—Device Symbol Editing A polygon outlining the symbol, used for highlighting and erasing the symbol. An optional internal circuit definition. The following sections deal with the creation and maintenance of library files. Later parts of this chapter deal with editing the symbols themselves. Creating a New Library To create a new, empty symbol library file, right-click anywhere in the Parts palette.
LW Reference.bk Page 137 Monday, December 15, 2003 5:59 PM Working With Symbol Libraries 137 Automatically Opening Libraries at Startup Libraries can be opened automatically when the program starts by any of these methods: Placing the library (or a shortcut to it) in the Libs folder inside the LogicWorks program folder. Placing a command in the LogicWorks initialization file (dw.ini) to specifically open the library using the LIBRARY or LIBRARYFOLDER setup file keywords.
LW Reference.bk Page 138 Monday, December 15, 2003 5:59 PM 138 Chapter 8—Device Symbol Editing Make sure the source and destination libraries are open in the Parts palette. If not, follow the steps under “Manually Opening a Library” on page 136. Select the Lib Maintenance command, either in the Libraries sub-menu of the File menu, or by holding the š key pressed while clicking in the Parts palette. Select the source library in the pop-up library selection menu above the “Source Lib” list.
LW Reference.bk Page 139 Monday, December 15, 2003 5:59 PM 139 Working With Symbol Libraries Click the Delete button. You will be prompted to confirm the operation before the items are permanently deleted. WARNING: The Delete operation cannot be undone! Duplicating a Symbol Within a Library You can duplicate a symbol within a single library by following these steps: Make sure the target library is open in the Parts palette. If not, follow the steps in “Manually Opening a Library” on page 136.
LW Reference.bk Page 140 Monday, December 15, 2003 5:59 PM 140 Chapter 8—Device Symbol Editing Click the Rename button. You will be prompted for each selected item to enter a new name. Names must be unique within a library. Getting Information on a Symbol in a Library You can display information on a symbol, such as the exact location of the source library and a summary of attribute values, by right-clicking on the item in the parts palette, then selecting the Properties command.
LW Reference.bk Page 141 Monday, December 15, 2003 5:59 PM Working With Symbol Libraries 141 Select the Lib Maintenance command. Select the library to be compacted as the Source Lib. Select the new, empty library as the Dest Lib. Click on the Compact button. IMPORTANT: Verify that the new destination library is correct before discarding the old copy. Operations on Symbols in a Schematic .
LW Reference.bk Page 142 Monday, December 15, 2003 5:59 PM 142 Chapter 8—Device Symbol Editing Using the Clipboard in Device Symbol Editor The standard Edit menu commands Cut, Copy and Paste can be used to move objects inside and between the symbol editor window, LogicWorks circuit windows, and other applications.
LW Reference.bk Page 143 Monday, December 15, 2003 5:59 PM Editing Device Symbols 143 Creating a New Part from Scratch—Basic Procedure To create a new device symbol with no initial attribute settings or graphics, either: Select the New command in the File menu, then choose the Device Symbol document type, or: Right-click in the Parts palette and select the New Part command.
LW Reference.bk Page 144 Monday, December 15, 2003 5:59 PM 144 Chapter 8—Device Symbol Editing This toolbar provides two types of pins: The first group allows placement of normal pins (i.e. not bus pins). The second group is used to place bus pins, i.e. pins that represent a group of named internal signals. NOTE: Since we are creating a discrete component symbol with no text on it, we should first disable the pin name display, which is on by default.
LW Reference.bk Page 145 Monday, December 15, 2003 5:59 PM Editing Device Symbols 145 pin list has been added for each pin. For this example we want to name the pins “Source”, “Gate”, and “Drain”. In addition we want to give them the following pin number “S”, “G”, and “D”. NOTE: Depending on the order in which you placed the pin symbols, they may not be in the list in the same order as this example.
LW Reference.bk Page 146 Monday, December 15, 2003 5:59 PM 146 Chapter 8—Device Symbol Editing Set the pin name and number for the other pins in a similar fashion. NOTE: Some netlist formats, notably SPICE, require that pins appear in a certain order in the output. Unless you specify otherwise using attributes, this order will be determined by the order in which the pins are placed on the symbol. Pins can be reordered by simply dragging them to a new position in the list.
LW Reference.bk Page 147 Monday, December 15, 2003 5:59 PM Editing Device Symbols 147 IMPORTANT: The procedure given here allows you to produce a symbol with only the simplest graphical and netlisting requirements.
LW Reference.bk Page 148 Monday, December 15, 2003 5:59 PM 148 Chapter 8—Device Symbol Editing save or discard the changes. Saving an Edited Part Back to its Original Library The Save command saves the contents of the current window back to the library it was read from. If the open part was not read from a library (i.e. it was just created), this item will be disabled.
LW Reference.bk Page 149 Monday, December 15, 2003 5:59 PM 149 Editing Device Symbols so. When installing future program upgrades, these libraries may be replaced automatically, erasing any changes you have made! Zooming the Symbol Editor Window The Reduce/Enlarge/Normal Size commands in the View menu allow you to adjust the scale at which an object is viewed. The default setting for the device symbol editor is to display objects at the same size as they will appear in the schematic at Normal Size.
LW Reference.bk Page 150 Monday, December 15, 2003 5:59 PM 150 Chapter 8—Device Symbol Editing The Add Pins command displays the following box: Pin names, and optionally their pin numbers, may be entered into the box. The pins are created and merged with the contents of the pin list when a carriage return or enter key is pressed or when the Add button is clicked. The Add Pins palette does not create graphic pins, only pins for the pin list. The created pins are merged with the names in the pin list.
LW Reference.bk Page 151 Monday, December 15, 2003 5:59 PM Editing Device Symbols 151 names A0 through A7. These pin names were also given pin numbers. The pin numbers 1 2 3 4 11 12 13 and 14 were assigned. It is also possible to skip a pin name when assigning pin numbers to a pin name sequence. Consider the previous example, if we didn't want to assign the number 11 but wanted all other pin names to get the same number, we would do the following: A0..7(1..4,,12..14) instead of A0..7(1..4 11..14).
LW Reference.bk Page 152 Monday, December 15, 2003 5:59 PM 152 Chapter 8—Device Symbol Editing Deleting Pins In a device symbol editor window, pins exist both in the graphic representation of the symbol and in the pin list. They have to be deleted from both places before they are completely removed from the part definition. To remove a graphical pin from the symbol, simply select it by clicking on it and delete it with the delete key in the usual way.
LW Reference.bk Page 153 Monday, December 15, 2003 5:59 PM Editing Device Symbols 153 dow. Attributes defined while in the device symbol editor will be associated with the part in the library. These will become the default attributes for the part when it is placed in a circuit. IMPORTANT: Only attribute fields that have a value are stored with the symbol. When you save the symbol to a library, any fields with null values are stripped off to save storage.
LW Reference.bk Page 154 Monday, December 15, 2003 5:59 PM 154 Chapter 8—Device Symbol Editing Never Visible This indicates that the field value should not be displayed when the device is placed, regardless of the design's Visible by Default setting for this field. This does not prevent the value from being displayed later, it just sets the initial state. TIP: You can set the default visibility independently for each attribute field defined in a design.
LW Reference.bk Page 155 Monday, December 15, 2003 5:59 PM Editing Symbol Graphics 155 Holding the key down forces the object to be vertical, horizontal, or the same on both axes. In other words, if you are drawing a rectangle, it will be forced to a square shape, an ellipse will be forced to a circle, and a line will be forced to vertical, horizontal or 45 degrees, whichever is closest to the current position. Holding the key down, disables the Snap to Grid option, if it is currently on.
LW Reference.bk Page 156 Monday, December 15, 2003 5:59 PM 156 Chapter 8—Device Symbol Editing change its characteristics, or you can select Properties first to set the default settings and then draw the item with the rounded rectangle tool. Drawing Text To draw text items: Click on the text tool (A) in the toolbar. Click in the desired starting location in the drawing area. Type the text on the keyboard. Click anywhere outside the text box to terminate entry.
LW Reference.bk Page 157 Monday, December 15, 2003 5:59 PM Editing Symbol Graphics 157 by one of these methods: Click on the object to select it, then select the desired command from the Rotate/Flip submenu in the Objects menu. Right-click on the object and select the desired command from the Rotate/ Flip submenu. Setting Grids The Grids command allows you to specify the visible grid spacing and the snapto grids for objects drawn using the drawing tools.
LW Reference.bk Page 158 Monday, December 15, 2003 5:59 PM 158 Chapter 8—Device Symbol Editing Pin Snap Spacing This number determines the snap-to grid for device pins. This must be a multiple of 5 to meet the LogicWorks pin grid requirements. The units are in screen dots at the default zoom level. Placing Pins on a Symbol The toolbar contains the tools needed to place connection pins on the symbol. The first group of pin tools is used to create normal pins (i.e.
LW Reference.bk Page 159 Monday, December 15, 2003 5:59 PM 159 Editing Symbol Graphics The Symbol Editor’s Pin List The pin list box contains a scrollable list of the pin names associated with this device. This list is derived from the following sources: If the symbol was opened from an existing part, then the initial name list will be the pin names associated with the part.
LW Reference.bk Page 160 Monday, December 15, 2003 5:59 PM 160 Chapter 8—Device Symbol Editing Showing, Hiding, Editing or Moving a Pin’s Name By default, when you place a pin on the symbol, the name of the pin is included in the symbol adjacent to the pin graphic. Here are a number of ways of changing this name display: To show or hide the pin name on one or more pins, select the pins on the symbol or in the pin list, then select the Properties command in the Objects menu.
LW Reference.bk Page 161 Monday, December 15, 2003 5:59 PM Editing Symbol Graphics 161 moved and set as desired. You then “link” it back to the pin by rightclicking on the text item and selecting the Link to Pin command. This associates it with the pin so that it again follows the pin when moved. IMPORTANT: The Link to Pin command searches for a pin with exactly the same name as the given text. You cannot link an arbitrary text item to any pin.
LW Reference.bk Page 162 Monday, December 15, 2003 5:59 PM 162 Chapter 8—Device Symbol Editing To add a bus pin to a symbol you need to perform two steps: Use the Add Pins command to add the bus pin to the pin list and specify its bus internal pins. This command is described in “Adding Sequential Pin Names” on page 149. Place the graphical bus pin using the techniques described in “Placing Pins on a Symbol” on page 158.
LW Reference.bk Page 163 Monday, December 15, 2003 5:59 PM Saving Frequently-Used Graphics and Pins 163 Hiding the Symbol Gallery Window To hide the Symbol Gallery panel, select the Symbol Gallery item in the View menu to uncheck it, or click the X “go away” box in the upper right corner of the panel. Using Elements from the Symbol Gallery To add an item displayed in the Symbol Gallery list to the symbol editing window, simply drag and drop it at the desired location.
LW Reference.bk Page 164 Monday, December 15, 2003 5:59 PM 164 Chapter 8—Device Symbol Editing page 251 for information on how to locate this item in the initialization file. Specifying a Symbol Gallery File The source of the items in the Symbol Gallery list is a single, standard LogicWorks library file that is specified in the INI file. See “Symbol Gallery Location” on page 251 for information on how to specify this item in the initialization file.
LW Reference.bk Page 165 Monday, December 15, 2003 5:59 PM Saving Frequently-Used Graphics and Pins 165 TIP: You can also set the pin name, number and function by right-clicking on the pin graphic or on the name in the list and selecting the Properties command. Setting the Pin Number A four character identifier is displayed in the pin number field. Even though this is referred to as a number it may contain any valid character. For example, “10”, “Q4”, “E123”, and “In” are all valid pin numbers.
LW Reference.bk Page 166 Monday, December 15, 2003 5:59 PM 166 Chapter 8—Device Symbol Editing as desired. c See “Showing, Hiding, Editing or Moving a Pin’s Name” on page 160 for more information. Reordering Pins in the Pin List Pins can be reordered in the list by simply clicking and dragging them to the desired new position. This pin order does not affect the graphical appearance of the symbol, but may affect netlists generated from schematics containing the symbol.
LW Reference.bk Page 167 Monday, December 15, 2003 5:59 PM Saving Frequently-Used Graphics and Pins Options menu. This dialog allows you to select among several different options: Create a subcircuit This is the default. It indicates that the part symbol, but don't store being made has no associated subcircuit, but a circuit with it yet it doesn't rule out that a subcircuit may be attached by the schematic capture section of LogicWorks. Import the port list This is similar to the No Subcircuit option.
LW Reference.bk Page 168 Monday, December 15, 2003 5:59 PM 168 Chapter 8—Device Symbol Editing Create a subcircuit symbol and select an open circuit to attach to it. Set to Symbol Only type, never has a subcircuit. Set to primitive type. Must be used with caution! This option prompts for an open circuit to associate with the part being created as its subcircuit. The circuit definition is saved with the part in the library.
LW Reference.bk Page 169 Monday, December 15, 2003 5:59 PM Saving Frequently-Used Graphics and Pins Lock subcircuit by default so the subcircuit can't be opened Locate a new subcircuit definition 169 This option has the effect of saying, “Yes. There is a subcircuit, but in general you don't want to go into it”. This causes the schematic capture part of LogicWorks to prompt to make sure it is really OK to enter the subcircuit before doing so.
LW Reference.bk Page 170 Monday, December 15, 2003 5:59 PM 170 Chapter 8—Device Symbol Editing of the symbol. Auto-creating Rectangular Symbols The Auto Create Symbol command will create standard rectangular symbols given a list of the desired input and output pin names. For maximum flexibility, the symbol generated consists of separate graphic objects and is completely editable after it is generated. The current settings for line width, fill patterns, color, text font, size and style, etc.
LW Reference.bk Page 171 Monday, December 15, 2003 5:59 PM Saving Frequently-Used Graphics and Pins 171 Items in a list can be separated by blanks or commas. Placing an extra commas between two items adds extra space between the pins on the symbol. Additional space can be added with more commas. Specifying Pin Type You can use a "|" notation to specify the type (e.g. input or output) of pin to be created. The default is input, if no type is specified.
LW Reference.bk Page 172 Monday, December 15, 2003 5:59 PM 172 Chapter 8—Device Symbol Editing from the circuit definition. Creating a Breakout A breakout is a special device that allows signals to be associated with a bus. It consists of 1 Bus pin, no internal pins, and N normal pins. Because the device type is breakout the normal pins will be connected to like named signals in the bus. Breakouts are normally created using the New Breakout command described in “Creating a Breakout” on page 38.
LW Reference.bk Page 173 Monday, December 15, 2003 5:59 PM Saving Frequently-Used Graphics and Pins 173 Simulator The type of the pin must be set correctly if simulations are to make sense. For signal sources like +5V, +15V, and Vss, a normal simulation would expect a logical value of 1 (True). For signal sources like Ground and Vdd, a logical value of 0 (False) is expected. This means the pin type should be “Tied High” or “Tied Low” (See “Setting the Pin Type” on page 165).
LW Reference.bk Page 174 Monday, December 15, 2003 5:59 PM 174 Chapter 8—Device Symbol Editing not important, but the internal pins must have the same name. Once the port connector is placed in a circuit its reference name is important, it must be the same as the parent's pin name. See “Bus Pin Name Matching” on page 54 for more information.
LW Reference.bk Page 175 Monday, December 15, 2003 5:59 PM Saving Frequently-Used Graphics and Pins 175 signal is an input to the block and that MEMW/ and MEMR/ are outputs: Select the first internal pin name from the symbol editor's pin list. In this example it is CLK. Use the pin function pop-up menu at the top of the list to select Output for the pin function. Click on the next pin in the list.
LW Reference.bk Page 176 Monday, December 15, 2003 5:59 PM 176 Chapter 8—Device Symbol Editing Creating Special-Purpose Symbols Assigning a Primitive Type NOTE: The Primitive type settings should only be used with a clear understanding of their functions. Primitive types are intended primarily for creating pseudo-devices (such as power and ground connectors) and for use with the LogicWorks simulator. See Appendix A — Primitive Device Pin Summary on page 233.
LW Reference.bk Page 177 Monday, December 15, 2003 5:59 PM 9 Menu Reference This chapter provides a complete guide to individual menu commands in LogicWorks. In order to give you rapid access to commands, LogicWorks has two different sets of menus: Pull-Down Menus—these are the normal File, Edit, and other menus that appear in the menu bar at the top of the application window.
LW Reference.bk Page 178 Monday, December 15, 2003 5:59 PM 178 Chapter 9—Menu Reference Design—This choice creates a new, empty circuit window. This can be used to create an entirely new design, to create a subcircuit that will later be associated with a device, or as a temporary area to edit a circuit scrap. There is no fixed limit on the number of designs that can be open at once, although the complete contents of all open designs must fit into available memory.
LW Reference.bk Page 179 Monday, December 15, 2003 5:59 PM LogicWorks File Menu Commands 179 Close Close closes the current document (text, design, or symbol). If the document is a design, all the Schematic windows associated with the current design are closed. If any changes have been made to your design since the last Open or Save, then you will be asked if you wish to save those changes. NOTE: A design may be associated with multiple windows if you have been working with subcircuits.
LW Reference.bk Page 180 Monday, December 15, 2003 5:59 PM 180 Chapter 9—Menu Reference Print Setup Presents the Print Setup dialog, which allows you to choose the size and orientation of printer paper you wish to use. Once chosen, this information will be stored with your design file and will affect the page outlines shown in the command and the Show Printed Page Breaks option in the Design Preferences command. NOTE: LogicWorks uses the printer drivers associated with Windows.
LW Reference.bk Page 181 Monday, December 15, 2003 5:59 PM Edit Menu Commands 181 Redo This command redoes the last Undone command. It will only be enabled immediately after an Undo operation. Any other editing operation will disable this item. Using the Clipboard The standard Clipboard commands Cut, Copy, and Paste can be used to move or copy circuit fragments—and graphical and text information— within a single circuit window, between multiple windows, and between different programs (e.g.
LW Reference.bk Page 182 Monday, December 15, 2003 5:59 PM 182 Chapter 9—Menu Reference IMPORTANT: Circuit structural information on the Clipboard is discarded when you quit the program. Only picture and text data is retained. You cannot use the clipboard to Copy and Paste circuit data between LogicWorks sessions—you must use disk files. Cut and Copy work on the currently selected group of circuit objects and will be disabled if no objects are selected.
LW Reference.bk Page 183 Monday, December 15, 2003 5:59 PM Edit Menu Commands 183 was pasted, the points marked X would be checked for connection to the existing circuit. NOTE: Connection “hit testing” can be disabled by holding down the key while clicking the mouse button (this also applies to single device placing). In this case, the circuit scrap is placed, but no connections will be made to adjacent items.
LW Reference.bk Page 184 Monday, December 15, 2003 5:59 PM 184 Chapter 9—Menu Reference Delete Removes the currently selected objects from the circuit. Pressing the or key on the keyboard is equivalent to Delete. This command will be disabled if no devices or signals are selected. Duplicate Makes a copy of the selected circuit group—which can be dragged and positioned as desired.
LW Reference.bk Page 185 Monday, December 15, 2003 5:59 PM Edit Menu Commands 185 Shortcuts to Point Since you will frequently want to return to Point mode, three shortcuts are provided for this purpose: Pressing the keyboard spacebar. Pressing the Escape key. Text The Text command changes the current cursor to text mode and is equivalent to clicking on the icon on the toolbar.
LW Reference.bk Page 186 Monday, December 15, 2003 5:59 PM 186 Chapter 9—Menu Reference Any of the above items can be edited by clicking anywhere in the existing object. The blinking insertion point will appear in the text at the position of the click. All of the above functions are described in more detail in Chapter 5, Schematic Editing. Zap The Zap command changes the current cursor to Zap mode, and is equivalent to clicking on the icon in the toolbar.
LW Reference.bk Page 187 Monday, December 15, 2003 5:59 PM View Menu Commands 187 drawing. To terminate signal drawing mode, double-click the left mouse button, then press the spacebar or click anywhere in the menu bar. See more information on signal drawing modes in Chapter 5, Schematic Editing. Draw Bus The Draw Bus command is equivalent to clicking on the icon in the toolbar. Bus-drawing mode behaves exactly like signal-drawing mode except that a bus line is created instead of a signal line.
LW Reference.bk Page 188 Monday, December 15, 2003 5:59 PM 188 Chapter 9—Menu Reference Normal Size When a circuit window is topmost, Normal Size sets the screen scale to 100%. Reduce To Fit Reduce to Fit sets the scale factor, and centers the display, so that the entire diagram fits in the window. Zoom In When a circuit window is topmost, Zoom In increases the scale factor, causing the diagram to appear larger on the screen.
LW Reference.bk Page 189 Monday, December 15, 2003 5:59 PM Schematic Menu Commands 189 played area. The circuit position and scaling will be adjusted to display the indicated area. Zooming Out Clicking and dragging the mouse up and to the left zooms out to view more of the schematic in the window. The degree of change in the scale factor is determined by how far the mouse is moved. Moving a small distance zooms out by one step (equivalent to using the Reduce command).
LW Reference.bk Page 190 Monday, December 15, 2003 5:59 PM 190 Chapter 9—Menu Reference The orientation can also be changed by: Clicking directly on the orientation tools in the toolbar, or Using the arrow keys on the keyboard. See more information about symbol rotation in Chapter 5, Schematic Editing. Get Info... The Get Info command is a general method of viewing and setting parameters and options that are associated with the various types of objects in LogicWorks.
LW Reference.bk Page 191 Monday, December 15, 2003 5:59 PM Schematic Menu Commands 191 The following items of information are shown. Counts apply only to the topmost circuit level in the design, regardless of any subcircuit windows that may be open. Devices This is a count of devices in the selected scope. Pseudodevices, such as ground symbols and breakouts, are not included. The count includes devices that have subcircuits.
LW Reference.bk Page 192 Monday, December 15, 2003 5:59 PM 192 Chapter 9—Menu Reference General Device Info Box When a normal device symbol is selected on the schematic (i.e., not a pseudo-device), then the following information box is displayed: The following table lists the information and options available in this box. Type This is the library type name of the device symbol, i.e., the name as it appears in the Parts Palette.
LW Reference.bk Page 193 Monday, December 15, 2003 5:59 PM Schematic Menu Commands Attributes ... NOTE: 193 This button displays the standard Attributes dialog for the device. Clicking Cancel in the Device Info dialog does not cancel any changes that you may have made in other windows that you displayed using this dialog’s option buttons. Pseudo-Devices If a pseudo-device is selected in the schematic, the Get Info command will be ignored.
LW Reference.bk Page 194 Monday, December 15, 2003 5:59 PM 194 Chapter 9—Menu Reference The following table describes the information and options presented in this box: Bus Signals This is a list of the signals contained in the bus. This list is determined by the breakouts and bus pins attached to the bus. You cannot directly change this list. See Chapter 6, Advanced Schematic Editing, for more information. Attributes This button displays the general Attributes dialog for the selected bus.
LW Reference.bk Page 195 Monday, December 15, 2003 5:59 PM Schematic Menu Commands 195 The following information and options are available: Pin Number This is the physical pin number corresponding to this device pin. This can be empty if desired. Visible This checkbox determines whether the pin number is displayed on the schematic. For some devices, such as discrete components, it may be desirable to have a pin number associated with the pin for netlist purposes without displaying it on the diagram.
LW Reference.bk Page 196 Monday, December 15, 2003 5:59 PM 196 Chapter 9—Menu Reference The following table summarizes the options available in this box. Rule Between Lines Checking this box causes a line to be drawn after each row of characters. Draw Frame Checking this box causes a frame to be drawn around the text item on the schematic. Font Specs... Clicking this button displays the standard font style dialog.
LW Reference.bk Page 197 Monday, December 15, 2003 5:59 PM Schematic Menu Commands Make Background 197 Selecting this option makes the picture into a background object. This means that it will not normally be selected by clicking on it. Background pictures can be selected by holding the and keys.. See more information on text objects in “Sheet Borders and Title Blocks” on page 32. New Breakout... The New Breakout command is used to generate a standard bus breakout symbol for a group of signals.
LW Reference.bk Page 198 Monday, December 15, 2003 5:59 PM 198 Chapter 9—Menu Reference Blanks or commas can be used to separate individual names in this list, therefore bussed signals cannot have names containing a blank or comma. A range of numbered signals can be specified using the following formats: D0..7 or D0..D7 is equivalent to D0 D1 D2 D3 D4 D5 D6 D7 D15..0 is equivalent to D15 D14 D13 D12 D11 D10 D9 D8 E D0 D15..
LW Reference.bk Page 199 Monday, December 15, 2003 5:59 PM Schematic Menu Commands 199 D0..15 AS* UDS* LDS* CLK FC0..3 MEMOP BRQ0..2 Pin Spacing The number in the Pin spacing box will be the spacing between signal pins on the breakout symbol, in grid units. The default value is 4 to match the standard LogicWorks libraries, but any number from 1 to 100 can be entered. Push Into This command opens the internal circuit of the given device in a separate window.
LW Reference.bk Page 200 Monday, December 15, 2003 5:59 PM 200 Chapter 9—Menu Reference See more information on internal circuits and type definitions in Chapter 6, Advanced Schematic Editing. Attach Subcircuit... This command allows you to select an open design to attach as a subcircuit to the selected device.
LW Reference.bk Page 201 Monday, December 15, 2003 5:59 PM Schematic Menu Commands 201 ing and has been modified. When you close the internal circuit, you will be asked if you wish to update other devices of the same type. Detach Subcircuit This command turns the currently displayed subcircuit into a separate design and redefines the parent device as having no internal circuit.
LW Reference.bk Page 202 Monday, December 15, 2003 5:59 PM 202 Chapter 9—Menu Reference Design Preferences... The Design Preferences command is used to set a number of options which have global effect throughout a design. Selecting this command displays the following dialog: Show Crosshairs When this option is enabled, moving crosshairs will follow all cursor movements to assist with alignment of circuit objects.
LW Reference.bk Page 203 Monday, December 15, 2003 5:59 PM Schematic Menu Commands 203 Print Background Grid When this option is enabled, the background grid lines will be drawn in printed output. Show Default Border When this option is enabled, a border will be displayed around the boundary of the page and will adjust automatically based on printer setup. Attribute Text Options Clicking on the Attr Text...
LW Reference.bk Page 204 Monday, December 15, 2003 5:59 PM 204 Chapter 9—Menu Reference Pin Text Options The Pin Text... button displays the same text specification box shown above for Attribute Text. Any changes made to this text style will be applied to all pin numbers displayed throughout the design. The text changes are applied when the OK button in the Design Preferences box is clicked.
LW Reference.bk Page 205 Monday, December 15, 2003 5:59 PM 205 Simulation Menu Commands Run This command tells the simulation to proceed as fast as possible. Other Simulation Speeds The intermediate speed settings between Stop and Run insert various amounts of delay between executing successive simulation time steps. These can be used to slow the simulation progress for convenient observation. Single Step This command simulates one time step.
LW Reference.bk Page 206 Monday, December 15, 2003 5:59 PM 206 Chapter 9—Menu Reference NOTE: 1) You cannot set the device delay of a subcircuit device since its general delay characteristics are determined by its internal circuit. If any subcircuit devices are selected, they will be ignored for device delay purposes. You can set the pin delay on subcircuit devices to modify the path delay through a particular pin.
LW Reference.bk Page 207 Monday, December 15, 2003 5:59 PM Simulation Menu Commands 207 Shortest / longest delay This shows the shortest and longest delays found in any of the selected devices or pins. (Note that each device or pin has only a single integer delay value associated with it.) Delay text box If all selected devices or pins have the same delay value, it is shown in this box. If a variety of values exist among the selected items, this box will be empty.
LW Reference.bk Page 208 Monday, December 15, 2003 5:59 PM 208 Chapter 9—Menu Reference High This text box allows you to edit the high time setting of the selected clock device. Allowable settings are in the range 1 to 32,767. See Chapter 9, Primitive Devices, for more information on how you can set the startup delay and initial value of a Clock device by setting the pin delay and inversion on the output pin.
LW Reference.bk Page 209 Monday, December 15, 2003 5:59 PM Simulation Menu Commands 209 Add to Timing This command adds all selected signals in the current circuit to the Timing display. If any selected items are unnamed or are already displayed, they will be ignored. New items are added at the bottom of the Timing display and will be selected after the add. Add Automatically When this item is checked, any signals added or edited on the schematic will automatically be added to the Timing window.
LW Reference.bk Page 210 Monday, December 15, 2003 5:59 PM 210 Chapter 9—Menu Reference The controls in the box are summarized in the following table. Selected Signals in Current Circuit If this option is selected, the Stick High, Stick Low, or Unstick option will apply only to signals currently selected in the Schematic diagram.
LW Reference.bk Page 211 Monday, December 15, 2003 5:59 PM LogicWorks Help Menu NOTE: 211 This command does not display or remove any traces in the Timing window. It only reads signal event data and associates it with matching traces. If any traces are named in the file that are not currently displayed, you will be warned and that set of data will be skipped. Export Timing (Text)... This command saves all the displayed data in the Timing window to a text file.
LW Reference.bk Page 212 Monday, December 15, 2003 5:59 PM 212 Chapter 9—Menu Reference LogicWorks Online A number of resources are available on the World Wide Web for LogicWorks users, including technical notes, FAQs, free downloads, add-on products, and so forth. These items will direct your Web browser directly to the corresponding Web page. You must, of course, have a connection to the Internet active for these menu items to work.
LW Reference.bk Page 213 Monday, December 15, 2003 5:59 PM Device Pop-Up Menu 213 Rotate and Flip Commands These four commands are equivalent to deleting the selected device and replacing it in the selected new orientation. If the new rotation causes any device pins to touch adjacent signal lines, connections will be made (unless the Control key is held). Cut This is equivalent to selecting the Cut command in the Edit menu while this device is selected.
LW Reference.bk Page 214 Monday, December 15, 2003 5:59 PM 214 Chapter 9—Menu Reference The Clipboard is not affected. Signal Pop-Up Menu A signal pop-up menu is displayed by using the right mouse button to select any signal line. Signal Info... This command displays the general signal information box. This is equivalent to selecting the signal and selecting the Get Info command in the Schematic menu. See more information on this command above. Attributes...
LW Reference.bk Page 215 Monday, December 15, 2003 5:59 PM Signal Pop-Up Menu 215 Apply to all connected signals This option allows you to choose whether the name change applies only to the selected signal segment (thereby breaking its connection with other like-named signals), or to all interconnected signal segments. Visible This option allows you to choose whether the entered name should be displayed on the schematic or not.
LW Reference.bk Page 216 Monday, December 15, 2003 5:59 PM 216 Chapter 9—Menu Reference Pin Pop-Up Menu A pin pop-up menu is displayed by using the right mouse button to select any device pin. NOTE: Since an unconnected device pin is both a pin and a signal, you determine whether you get the pin or signal pop-up menu as follows: Clicking on the pin in the last 1/4 of the pin length away from the device will display the signal menu.
LW Reference.bk Page 217 Monday, December 15, 2003 5:59 PM Pin Pop-Up Menu 217 Attributes... This command displays the standard Attributes dialog for fields associated with the selected pin. The Prev Pin and Next Pin buttons on this box can be used to view and edit other pins on the same device without having to return to the schematic and select them individually. Bus Pin Info... This pop-up menu item will be enabled only when a bus pin on a device is selected.
LW Reference.bk Page 218 Monday, December 15, 2003 5:59 PM 218 Chapter 9—Menu Reference signal can only connect to one pin and vice versa). The signal list will be updated to show the new relationship. The Join Sequential button provides a quick method of joining multiple numbered pins and signals. The selected pin is joined to the selected signal, as with Join, above. If the signal and pin names both have a numeric part, both numbers are incremented and the corresponding signal and pin are joined.
LW Reference.bk Page 219 Monday, December 15, 2003 5:59 PM Circuit Pop-Up Menu 219 The order of entry will affect the order in which the signals appear in the list, but is otherwise not significant. For a complete description of the rules of this format, see the New Breakout command elsewhere in this chapter. NOTE: These signals are only added temporarily. When you close the Bus Pin Info box, all signals that are not connected to any pin are removed from the bus.
LW Reference.bk Page 220 Monday, December 15, 2003 5:59 PM 220 Chapter 9—Menu Reference Circuit Info... This command is equivalent to the Get Info command in the Schematic menu while no items are selected in the current circuit. It displays the circuit info box. Attribute Pop-Up Menu When any visible attribute data item on the schematic is right-clicked, the Attribute pop-up menu will appear.
LW Reference.bk Page 221 Monday, December 15, 2003 5:59 PM Attribute Pop-Up Menu 221 The selected point on the text is considered to be the reference point for the given attribute block. This point will be kept fixed if any field value or text style changes cause the box to be resized. Hide This command causes the visible attribute text that was selected to be removed from the schematic without removing the value from the field.
LW Reference.bk Page 222 Monday, December 15, 2003 5:59 PM 222 Chapter 9—Menu Reference Library Manager Submenu This menu can be displayed by clicking the right mouse button in the Parts Palette. Edit Part The Edit Part command opens the selected part in the device symbol editor. NOTE: If you edit any of the parts supplied with LogicWorks, you should save the modified version to your own library.
LW Reference.bk Page 223 Monday, December 15, 2003 5:59 PM Library Manager Submenu 223 Close Lib... Close Lib... allows you to close an open library and remove it from the Parts Palette. Any information required for parts used in any open designs will be automatically retained in memory. When you select the Close... command, a box will appear listing the open libraries. Pick one by clicking on it and then press the Close button, or simply double-click on the name of the library. Lib Maintenance...
LW Reference.bk Page 224 Monday, December 15, 2003 5:59 PM 224 Chapter 9—Menu Reference Copy This button causes the selected parts in the Source Lib list to be copied to the Dest Lib. Delete This button causes the selected parts in the Source Lib to be deleted. This cannot be undone! Duplicate This causes the selected parts in the Source Lib to be duplicated—i.e., a copy of the selected items is made in the Source Lib. The Dest Lib is not affected.
LW Reference.bk Page 225 Monday, December 15, 2003 5:59 PM Device Editor Objects Menu Commands 225 Device Editor Objects Menu Commands Bring To Front / Send To Back These commands are used to set the front-to-back ordering of the selected objects, relative to the other graphic objects. Group / Ungroup The Group command causes DevEditor to treat multiple selected graphic objects—except pins—as a single object. The Ungroup command disaggregates a grouped object.
LW Reference.bk Page 226 Monday, December 15, 2003 5:59 PM 226 Chapter 9—Menu Reference Device Editor Options Menu Commands Grids... This command allows the user to specify the visible grid spacing, and the snap-to grids for objects drawn using the drawing tools. The following table summarizes the options available: Grid Visible This checkbox determines whether visible grid lines are shown in the drawing workspace of the DevEditor window.
LW Reference.bk Page 227 Monday, December 15, 2003 5:59 PM Device Editor Options Menu Commands 227 Add Pins This command brings up the Add Pins palette allowing you to add multiple pins to the DevEditor’s pin list. See Chapter 11, Device Symbol Editing, for more information. Autocreate Symbol This command brings up the automatic symbol creation dialog, allowing you to automatically generate a rectangular device symbol. See Chapter 11, Device Symbol Editing, for more information.
LW Reference.bk Page 228 Monday, December 15, 2003 5:59 PM 228 Chapter 9—Menu Reference Text Font... This menu command displays a dialog box allowing the font, style, and size for the selected text objects to be set. If no objects are selected, then the selected text property becomes the new default. Text Rotation These menu items set the rotation characteristics for the selected text objects. If no objects are selected, then the text property you set becomes the new default.
LW Reference.bk Page 229 Monday, December 15, 2003 5:59 PM Timing Trace Pop-up Menu Commands 229 Paste The Paste command pastes the Timing text data from the Clipboard onto the selected area of the Timing window. The following rules are used for matching the data on the Clipboard with the selected interval in the Timing window: Data is always pasted by name, i.e., the name of a signal in the Clipboard data will be matched to the same-named signal in the Timing window.
LW Reference.bk Page 230 Monday, December 15, 2003 5:59 PM 230 Chapter 9—Menu Reference Display On This command enables updating of the Timing display. Display Off This command disables updating of the Timing display. Events are saved but are not drawn into the Timing window. This allows simulation to proceed at a substantially faster rate. Normal Size This command sets the horizontal display resolution to its initial defaults.
LW Reference.bk Page 231 Monday, December 15, 2003 5:59 PM Timing Trace Pop-up Menu Commands 231 Timing Data Retention These options allow you to determine how much signal-event data is retained in memory when a simulation is run. Each time a signal level change occurs LogicWorks creates a record in memory containing a reference to the signal, time, new value, and source of the change. In a large simulation these records can consume enormous amounts of memory.
LW Reference.bk Page 232 Monday, December 15, 2003 5:59 PM 232 Chapter 9—Menu Reference Timing Label Popup Menu Commands Get Info... For groups, this command displays a dialog allowing reordering of the signals in the group. This affects the way the combined hexadecimal value is shown in the timing display. For individual signals, a signal info dialog is displayed.
LW Reference.bk Page 233 Monday, December 15, 2003 5:59 PM Appendix A— Primitive Device Pin Summary This appendix lists all the primitive types used in LogicWorks and the allowable numbers and types of pins on each. For more information on using the Device Symbol Editor to assign a primitive type, see “Assigning a Primitive Type” on page 176. Schematic Symbol Primitive Types Primitive Type Pin Requirements Comments SUBCIRCUIT No restrictions Symbol having an optional internal circuit.
LW Reference.bk Page 234 Monday, December 15, 2003 5:59 PM 234 Appendix A— Primitive Device Pin Summary Pseudo-Device Primitive Types IMPORTANT: The pin requirements listed in the following table must be followed when creating pseudo-device symbols. These rules are not checked by the DevEditor. . Primitive Type Pin Requirements Comments BREAKOUT Pin 1 is Bus Pin, followed by N Normal Pins, set to Input Splits signals out of or into a bus.
LW Reference.bk Page 235 Monday, December 15, 2003 5:59 PM 235 Simulation Primitive Types Simulation Primitive Types For more information on the simulation primitive types, see “Primitive Devices” on page 95. NOTE: IMPORTANT: The following table lists the pin functions and orders for all simulation primitive device types. In some cases, a number of pins can be optionally omitted, so the table gives rules rather than enumerating all possible combinations.
LW Reference.bk Page 236 Monday, December 15, 2003 5:59 PM 236 Appendix A— Primitive Device Pin Summary Multiplexer L select inputs M output bits 1 N inputs/ output 2L-1 < N L ( i.e., the number of inputs per output bit can be less than the number of select input combinations.) S0..SL-1—in IN0,0..INN-1,M-1 —in * EN—in ¤ OUT0..OUTM-1— out 1) IN0,0..IN0,M-1 IN1,0..IN1,M-1 .. INN-1,0..INN-1,M-1 S0..SL-1 OUT0..OUTM-1 2) IN0,0..IN0,M-1 * INn,m is the input IN ..IN 1,0 1,M-1 .. routed to output m IN ..
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LW Reference.bk Page 238 Monday, December 15, 2003 5:59 PM 238 Appendix A— Primitive Device Pin Summary Shift Register N output bits N input bits 1 One Shot IN0..INN-1—in CLK—in LD—in CIN—in OUT0..OUTN-1 —out 1) IN0..INN-1 OUT0..OUTN-1 CLK LD CIN 2) OUT0..
LW Reference.bk Page 239 Monday, December 15, 2003 5:59 PM Appendix B— Device Pin Types Every device pin has a characteristic known as its pin type. The pin type is set when the part entry in the library is created and cannot be changed for individual device pins on the schematic. Refer to Chapter 11, Device Symbol Editing, for information on how to set the pin type while creating a device symbol.
LW Reference.bk Page 240 Monday, December 15, 2003 5:59 PM 240 Appendix B— Device Pin Types Pin Types Table The following table lists the function of each of the pin types available in LogicWorks. The Output Value Mapping column specifies how output values specified by the model are mapped to actual pin drive values. Pin Type Description Initial Value IN Input—this is the default for pins created HIGHZ using the DevEditor tool.
LW Reference.bk Page 241 Monday, December 15, 2003 5:59 PM 241 Device Pin Type and Simulator Efficiency Pin Type Description Initial Value LTCHIN Input to a transparent latch—this is used for HIGHZ calculating cumulative setup and hold times. Output Value Mapping No output drive allowed. LTCHOUT Output from a transparent latch—this is used for calculating cumulative setup and hold times. DONT01 Same as OUT.
LW Reference.bk Page 242 Monday, December 15, 2003 5:59 PM 242 Appendix B— Device Pin Types device. On subcircuit devices, the simulator must make several passes through all circuit levels that may affect the value of the signal or may be affected by it. Setting a pin on a subcircuit device to be an input or output greatly reduces this overhead.
LW Reference.bk Page 243 Monday, December 15, 2003 5:59 PM Appendix C— Initialization File Format (for Windows) In Windows, you can specify startup options for LogicWorks by creating or modifying an external text file called lw.ini. Use of this file is completely optional: if LogicWorks does not detect its presence, the program will start up with factory defaults. If you choose to create or modify an initialization file, observe the following conventions: The file should be called lw.
LW Reference.bk Page 244 Monday, December 15, 2003 5:59 PM 244 Appendix C— Initialization File Format (for Windows) Default System Font Font = “font_name” font_size [BOLD ITALIC] This statement specifies the default font which the LogicWorks system will use when no other font has been specified. Certain Tool modules may, by default, display text using this font. If no font is specified, an attempt is made to use a Courier typeface. If no font size is specified then 10 point is used.
LW Reference.bk Page 245 Monday, December 15, 2003 5:59 PM [System Font Translations] Section 245 [System Font Translations] Section Old_Font_Name = Replacement_Font_Name Font translations are used when the fonts embedded in a file are not available on the current platform. This section allows the user to define which fonts (available on the current platform) are to be used instead of the specified fonts. The replacement font must be a TrueType font. Each line in this section specifies a font mapping.
LW Reference.bk Page 246 Monday, December 15, 2003 5:59 PM 246 Appendix C— Initialization File Format (for Windows) optional style keywords which may be applied, BOLD and ITALIC. The possible items which may have their font specified are: Default_Font Attribute_Font, Border_Font, MiscText_Font, Pin_Font, Symbol_Font Color Settings XXX_Col =RED, GREEN, BLUE, CYAN, MAGENTA, YELLOW BLACK, DKGRAY, GRAY, LIGHT GRAY, WHITE This statement specifies the color for an item(s) appearing in a schematic document.
LW Reference.bk Page 247 Monday, December 15, 2003 5:59 PM [Drawing] Section 247 Disabling Untitled Design at Startup This statement controls the creation of a new untitled design when the program is first started. If the NOUNTITLED statement has a value of On, the program will start up and just display its menus, with no default window opened. The default is Off.
LW Reference.bk Page 248 Monday, December 15, 2003 5:59 PM 248 Appendix C— Initialization File Format (for Windows) Pin Spacing PINSPACE = n; The PINSPACE keyword is used to specify the spacing between adjacent pins when breakout symbols are created. This can also serve as the default for symbols created by other tools. The value must be a single decimal integer, which the program will use as a multiple of the standard grid space of 5 pixels. The default value is 2, which yields a spacing of 10 pixels.
LW Reference.bk Page 249 Monday, December 15, 2003 5:59 PM [Libraries] Section 249 Undo Levels The UNDO keyword indicates the number of levels of Undo which should be maintained. A value of zero means that there is no Undo. The format of this command is: UNDO = n Fine-Tuning Pin Number Text Display The PINTEXT keyword allows you to adjust the display position of pin numbers on devices. The format of this keyword is as follows: PINTEXT = dth dtv . . .
LW Reference.bk Page 250 Monday, December 15, 2003 5:59 PM 250 Appendix C— Initialization File Format (for Windows) This specifies the folder/directory that will contain the libraries specified in following LIBRARY statements. This statement can be omitted if the libraries are located in the same directory as the LogicWorks executable, or if you prefer to specify a complete library path in each Library statement. Single Library LIBRARY = library_path This specifies a single library to open.
LW Reference.bk Page 251 Monday, December 15, 2003 5:59 PM Section [DevEditor] 251 There are two optional style keywords which may be applied, “BOLD” and “ITALIC”. Grid Settings GridColor =RED, GREEN, BLUE, CYAN, MAGENTA, YELLOW BLACK, DKGRAY, GRAY, LTGRAY, or WHITE GridSize = grid SnapSize = snap PinSnapSize = pinsnap The GridColor statement specifies what color to use when drawing the symbol editor’s Grid. GridSize, SnapSize and PinSnapSize are all expressed as a 5 pixel multiplier.
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LW Reference.bk Page 253 Monday, December 15, 2003 5:59 PM [DevEditor] Section The options below allow you to customize the look and feel of the DevEditor tool. Default Font Font = “font_name” font_size [BOLD ITALIC] This statement specifies the default font for text items appearing in a DevEditor document. The “font_name” parameter is the name of a TrueType font; only TrueType fonts are supported. The font_size parameter is the point size to use.
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LW Reference.bk Page 256 Monday, December 15, 2003 5:59 PM 256 Appendix D— Timing Text Data Format When you Copy or Cut a selected area in the Timing window, two types of data are placed on the system Clipboard: A picture of the selected area, in LogicWorks’ internal format. This picture is not available to outside applications. A text description of the signal value changes occurring in the selected area.
LW Reference.bk Page 257 Monday, December 15, 2003 5:59 PM Data Line Format 257 The header always contains the command “$T” (denoting a time column), followed by a tab character, followed by “$D” (denoting a delay column). The remaining items depend on the traces that were selected in the Timing window. NOTE: The Timing tool always places the time and delay items in the order given here, although it will accept data with these items present in any order, or even completely missing.
LW Reference.bk Page 258 Monday, December 15, 2003 5:59 PM 258 Chapter — The delay from this step to the next step. This is redundant information, since it can be derived from the times in the first column. It is provided for compatibility with TestPanel and for improved flexibility in exporting to outside software systems. NOTE: 1) If the delay and time columns do not match, the longest time is used.
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