INTRODUCTION This manual is designed to help you quickly and easily learn to use your Quantum Composers Model 9412/9412A pulse generator. Rather than the usual array of knobs and switches, the 9412/9412A uses a menu-driven user interface with "on-line" help -- once you learn the basics of operating your 9412/9412A, you may never need to refer to this manual again.
Custom Modifications The 9412/9412A is microprocessor-controlled and employs a flexible and expandable userinterface. New features and operating modes often can be added, without hardware modifications, by merely modifying the software contained inside the 9412/9412A. Most modific ations can be made for a very modest charge -- contact Quantum Composers for details.
6. Never work alone. Someone should always be nearby to render aid if necessary. Training in CPR first aid is highly recommended.
Item Button 1 5
1 CONTROLS AND CONNECTORS This chapter explains the function of each control and connector on the 9412/9412A. Front Panel The front panel contains the most frequently used controls and connectors. Display The 9412/9412A features a backlit liquid crystal display, which displays menu selections and settings. The left half of the display shows the current menu selection, while the right half shows the current setting of the item associated with that menu.
Left Button (help) For numeric items, this button is used to select which digit in a numeric entry is selected for editing. For other items or when the left most digit is already selected for numeric items, pressing and holding this button down displays a brief description of the current item. Right Button (range) For numeric items, this button is used to select which digit in a numeric entry is selected for editing.
T2 Channel 2 output -- designed specifically for use as a solid-state laser Q-switch trigger and has all the capabilities of the other output channels, including several special modes which affect only the output of Channel 2. Ext/Gate External Trigger or Gate signal input -- used as either an external signal to trigger the generation of pulses or as a gate signal to enable and disable the outputs.
1 10
1 11
1 OPERATING INSTRUCTIONS This chapter presents detailed instructions on the operation of the 9412/9412A. Overview The 9412/9412A uses a single -line LCD to display menu selections. The front panel keys are used to "navigate" through sets of menus to set various options and control the pulse generator. Some keys are only active at certain times or have different behavior depending on what state the menus are in -- once understood, the menus can be quickly and easily manipulated.
Main Menu The Main Menu consists of a set of menu selections used to set the operating mode, time period and frequency of the 9412/9412A. MODE - Pulse Modes There are five (5) different Pulse modes available. Continuous Mode While in Continuous mode, the 9412/9412A will generate pulses at the rate set by the internal To Period as set in the ToPer menu. The delay of Channel 1 is relative to To, while the delay for Channel 2 is from the active edge of Channel 1.
Duty Cycle The Duty Cycle mode is similar to Continuous mode in that a continuous stream of pulses is output. The exception is the outputs are only active for a set number of seconds (DC:On menu), then disabled for another set time period (DC:Off menu) before being re-enabled. This cycle is repeated for a set number of times (CYCLES menu), after which all outputs cease. Setting the number of cycles to zero results in continuous cycling, until the Stop Key is pressed.
ToPer - To Period Except when in External Trigger or Single Shot mode, all pulse outputs are based on an internal timer called To. This menu is used to select the rate at which To runs by selecting the time period in microseconds between timer pulses. When in Continuous, Burst, or Duty Cycle mode, pulses are output at the rate determined by To. The frequency of pulse outputs in these modes can be found by taking the reciprocal of the To Period setting.
When set to Positive , the output will initially be at 0 Volts. When active, will go high for the specified pulse width time, after which it will return to 0. The voltage level while high will depend upon the load and the setting of the output voltage adjustment on the back panel. If set to Negative , the output will normally be at the high voltage level. When the output is activated, it will go to 0 Volts for the specified pulse width time, after which it will return to the high level again.
T2:Wait The output of Channel 2 can be delayed for a number of pulses. This menu is used to set the number of pulses that must occur on the other channels before the output of Channel 2 is enabled. This is particularly useful when using Channel 2 as a Q-switch trigger, as it allows the laser to thermally stabilize before activating the Q-switch. This function is active only in Continuous, Burst, and Duty Cycle modes.
RECALL Configuration Recalls a previously stored configuration from the specified memory location. To recall a configuration use the Up and Down arrow keys to select the memory location number and press the Left or Right arrow key. You will be prompted to press the key to verify that you want to overwrite the active configuration. If you press any other key, the configuration will not be recalled. Note: A zero configuration is available for recall.
5 4 9 1 20 3 8 2 7 1 6
1 COMPUTER INTERFACE The 9412/9412A comes standard with an RS232 serial interface. All menu settings can be set and retrieved over the computer interface using a simple command language. Serial (RS232) Pinout The serial port is located on the back of the 9412/9412A and uses a 9-pin D-type connector with the following pinout (as viewed from the back of the 9412/9412A): 1. 2. 3. 4. 5. 6. 7. 8. 9.
P CR is a carriage return character (ASCII value 13). With echo enabled, all characters sent will be echoed back to the sender. Unidentified commands and most out of range conditions result in the pulse generator ignoring the command. If the command is properly identified, the pulse generator returns an ok followed by a carriage return and a line feed (ASCII 13, ASCII 10), otherwise it returns a ?1 (a question mark, followed by the number "one", a carriage return and a line feed).
Communication Protocol Communication parameters are set at 9600 baud, 8 bits, parity = none, and 1 stop bit. To help establish RS232 communications, the pulse generator emits the characters QC approximately every 200 ms after power up and until the 9412/9412A receives a $.
Command List The following table summarizes all the commands. Note: The name of each command is identical to how it appears on the display of the 9412/9412A.
Command Name MODE GATE ToPer DC:On DC:Off TRIG CYCLES #/BURST T1:Wid T1:Dly T1:Pol T2:Wid T2:Dly T2:Pol 9412/9412A Communication Commands Parameters Description 0 = Continuous mode 1 = Burst mode 2 = Duty Cycle mode 3 = Single Shot mode 4 = External Trigger mode 0 = off 1 = active low 2 = active high 1000 - 99999999 µs 500 - 99999999 µs (400B) 1 - 10000 Sec 1 - 10000 Sec 0 = falling edge 1 = rising edge 0 - 10000 cycles 1 - 50000 pulses 1 - 99999999 µs 0 - 99999999 µs 0 = Negative (active low) 1 = Positi
9412/9412A Communication Commands RECALL STORE SHOTS 0 - 4 (9412) 0 - 8 (9412A) 1 - 4 (9412) 1 - 8 (9412A) 0 = Reset to zero (9412A Only) ECHO Fmark, VOLUME 0 = Disable 1 = Enable 0 = , (comma) 1 = . (period) 0-9 Recall a stored configuration. Store a configuration. Resets shot counter. SHOT ? will return the number of shots. Enables/Disables the RS232 echo. The result string is always sent back. Sets the character used as a decimal point on the display. Sets the key click volume level.
1 SPECIFICATIONS DELAYS P CHANNELS Two (2) independent outputs, with digitally controlled delay and pulsewidth. P DELAY 0 to 99.999999 sec P PULSEWIDTH 10 µs to 99.999999 sec P RESOLUTION 1 µs P ACCURACY 100 ns + .0002 x delay P TIMEBASE 8 MHz, 50 PPM crystal oscillator P RMS JITTER 50 ns + .
OUTPUTS (T1,T2) P IMPEDANCE 50 Ω P SLEW RATE > .2 V/ns P OVERSHOOT < 100 mV + 10% of pulse amplitude P AMPLITUDE load manually adjusted, 1-10V into 50Ω load P PEAK CURRENT 400 mA per channel P AVERAGE CURRENT 200 mA average (total for all channels) 2-20V into high impedance all outputs at same level COMPUTER INTERFACE P RS232 trolled over the interface bus. 9600 Baud.
1 MAINTENANCE Except for fuse replacement, the 9412/9412A should require no maintenance. Replacing the Fuse The fuse is mounted on the circuit board located inside the 9412/9412A. Remove the top cover to access and follow the instructions given below to replace the fuse: 1. Unplug the 9412/9412A from power source and remove power cord from the back panel. 2. Remove the two screws located on the sides of the 9412/9412A (they hold the front plastic bezel in place) and remove bezel. 3.
1 CUSTOM FEATURES None.
