VT1538A ENHANCED FREQUENCY/TOTALIZE/ PWM SIGNAL CONDITIONING PLUG-ON USER’S MANUAL 82-0093-000 Release April 28, 2003 VXI Technology, Inc.
VXI Technology, Inc.
www.vxitech.com INTRODUCTION On May 1, 2003, VXI Technology, Inc. acquired Agilent Technology’s mechanical data acquisition product segment. During the transition period, Agilent branded manuals will be provided with the dynamic and static data acquisition products until the manuals have been rebranded. The following products are provided for in this manner.
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Agilent 75000 Series C Agilent Technologies E1538A Enhanced Frequency/Totalize/PWM Signal Conditioning Plug-on User’s and SCPI Programming Manual Where to Find it - Online and Printed Information: System installation (hardware/software) ............VXIbus Configuration Guide* Agilent VIC (VXI installation software)* Module configuration and wiring .......................This Manual SCPI programming .............................................This Manual VXIplug&play programming ..........................
Agilent E1538A Enhanced Frequency/Totalize/PWM SCP About this Manual This manual describes how to configure the Signal Conditioning Plug-on (SCP) using SCPI commands and explains the capabilities of this SCP. The contents of this manual are: • Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 4 • Identifying the Plug-on (IMPORTANT) . . . . . . . . . . . . . . . page 5 • Setting Configuration Switches . . . . . . . . . . . . . . . . . . . . . page 6 • Installation.
Introduction The Agilent E1538A provides eight TTL compatible channels of digital I/O. Channels can be individually configured to perform any one of the following functions: • Input: -- Static digital state -- Frequency measurement -- Period meaurement -- Totalize positive or negative signal transitions -- Pulse width measurement -- Rotational velocity (senses added or missing cogwheel teeth) -- Quadrature position.
both full and half step modes.(requires 2 or 4 channels) The logical sense of input and output channels can be configured as inverted or normal. Input-configured channels have individually programmable threshold levels that can range from -46V to +46V. Identifying the Plug-on (IMPORTANT) There are two versions of the E1538A. The early version does not support a PERiod measurement command set. Early versions have ROM revision February 1998 and earlier.
Setting Configuration Switches The SCP has three packages of eight switches each. The package labeled OE (Output Enable) determines a channel’s I/O direction. The package labeled PU (pull-up) controls whether or not a channel is floating or pulled up to an internal 5V supply. The package labeled VRS (for channels 0 and 1 only) can enable special input signal conditioning compatible with variable reluctance sensors. For a discussion on using the VRS mode, see "VRS Mode Input Operation" on page 10.
Installation Installation for this Plug-on is identical to other SCPs and is covered in Chapter 1 of your Agilent E1415 or E1419 User’s Manual. Connecting To The Terminal Module The SCP connections for the Terminal Modules are shown on the self-adhesive labels that come with the SCP. Use these to label terminal definitions on your terminal module. The connections are shown in Figure 3. Figure 3. E1538A Terminal Module Connections Figure 4 shows the screw terminal Option 11 for the E1419A.
Figure 4. E1419A Option 11 Terminal Module Connections Recommended Signal Connections Figure 5 shows the recommended method of wiring digital I/O channels, as well as the maximum voltage limitations for the E1538A. Figure 5 shows the shields connected directly to the E1415 ground. This is to limit potential noise on the digital wiring from affecting low-level analog channel wiring within the Terminal Module. Note The G (analog guard) terminals are connected through 10K Ohm resistors to chassis ground.
Figure 5. Recommended Connections and Voltage Limits Input and Output Characteristics This section describes the E1538’s channel input and output electrical characteristics. Refer to Figure 6 for the following discussions. Input Characteristics When configured for input, E1538 channels provide digital input through the threshold comparator. The digital input threshold level is programmable with a SCPI command from -48 to +47.625 VDC in .375V steps (relative to the Lnn terminal).
is to maintain a constant-level digital output while the input varies from millivolts to several tens of volts. For simple sensing of switches and open collector logic devices, a channel’s pull-up resistor can be connected by closing its PU switch. Figure 6.
(V – 17.5 ) 0.0032 sensor - to calculate the protection resistor’s value. formula R external = -------------------------------------- Figure 7 shows the VRS mode input characteristics. Figure 7. VRS Mode Input Characteristics Output Characteristics The output stage of the E1538A is simply a MOS FET transistor that is configured as "open-drain" when the pull-up resistor is not connected (PU switch is OFF).
Checking the ID of the SCP To verify the SCP type(s) installed on your VXI module, use the SYSTem:CTYPe? (@) command. • The channel parameter specifies a single channel in the channel range covered by the SCP of interest. The first channel number for each of the eight SCP positions are; 0,8,16,24,32,40,48, and 56.
• Channels in must be input configured channels Determining the Input Threshold Level Note To determine a channel’s input threshold level, use the command: INPut:THReshold:LEVel? (@) Because the E1538 rounds to the nearest multiple of 0.375, the returned value can be different from the value sent. • must specify a single input-configured channel. • INP:THR:LEV? returns a numeric value between -46 and +46. The C-SCPI type is int32.
Reading Static Digital State This means reading a channel’s current digital state when an algorithm executes. This is the default function assigned to all digital input channels after *RST and at power-up. To set individual channels to this function use the SCPI command [SENSe:]FUNCtion:CONDition (@). The value returned to an algorithm is a floating point representation of 0 or 1, depending on the state of the input signal and the channel’s INP:POL setting.
Totalize Positive or Negative Edge State Changes Use [SENSe:]FUNCtion:TOTalize (@) to configure channels to totalize. Totalize means to simply count state transitions (either positive going, or negative going). Figure 9 A shows totalizing transitions between each algorithm execution. Figure 9 B shows totalizing all transitions starting from the time the module last received an INITiate command.
About Period and Frequency Measurements The E1538A actually measures signal period for both the period and frequency functions. If the measurement function is set to frequency rather than period, the SCP returns the reciprocal of the measured period. The resolution of each period measurement is based on the time processor chip’s timer period (238.4nS). To improve resolution on faster input signals, multiple signal periods can be measured and averaged.
Measure Frequency Use [SENSe:]FREQuency:APERture
Measure Period Use [SENSe:]PERiod:MODe APERture | NPERiods,(@) to select the measurement interval setting mode. Depending on the mode selected above use [SENSe:]PERiod:APERture
To measure period at channel 45 as the average of 1000 signal periods: *RST TRIGGER:TIMER .2 SENS:FUNC:PER (@145) SENS:PER:RANGE 1,(@145) SENS:PER:MODE NPER(@145) SENS:PER:NPER 1000,(@145) ALG:DEF ’ALG1’,’writecvt(I145,45);’ INIT do loop SENS:DATA:CVT? (@45) read value from CVT query above end loop Alg executes at .
Measure Pulse Width This means that the E1538 will measure the width of the logic 1 portion of a pulse. The pulse width is sent to the algorithm in units of seconds. To measure the high portion of a pulse (positive going edge to negative going edge) set the channel input polarity to INP:POL NORM,(@). To measure the low portion of the pulse (negative going edge to positive going edge) set the channel input polarity to INP:POL INV,(@).
Sense Quadrature Position This means that the E1538 will convert a digital quadrature signal pair into an absolute 24-bit count. The count value can be read by the algorithm. The E1538’s quadrature position function increments a counter value each time there is a transition on either of the quadrature channel pair. When the lower numbered channel’s signal LEADS the higher numbered channel, the function counts up. When the lower numbered channel LAGS the higher numbered channel, the function counts down.
Figure 13. Sense Quadrature Position Sense Rotational Velocity This means that the E1538 will read the rotational velocity of a toothed wheel sensor. The E1538 measures tooth-to-tooth period and converts it into units of revolutions per second (RPS). This function can only be linked to the E1538’s first channel. The function works for wheels that have either a missing, or an extra tooth to mark their index position.
• can be either of the strings "MISSing", or "EXTRa" • must be the first channel on the SCP, but can contain more than one channel provided that each channel is on a separate E1538. See following note. The related Error Messages are: 3110, "Channel specified is invalid for RVELocity function. Note Only one channel on any E1538 SCP can be assigned to the SENS:FUNC:RVEL function, and it must be the first channel on the SCP." Figure 14.
Programming Output Channels Controlling Output Polarity This section deals with all aspects of programming output channel functions. Channels are configured for output with the I/O direction switches (see "Configuring Input-Output direction" on page 6). A related error message: 3124, "E1538 OE switch OFF conflicts with this command." Use OUTPut:POLarity NORMal | INVerted,(@) to configure output channel logic sense.
Variable Width Pulse Per Trigger This means that the channel generates a pulse whose width is specified by the algorithm each time the algorithm executes. The value sent by the algorithm can range from 7.87µSec to 7.812mSec. The command sequence to set-up this mode is: SOURce:FUNCtion:PULSe (@) to enable pulse generation. the following two commands return the E1538 to the Single pulse-per-trigger mode from either the FM or Pulse Width Modulation modes.
Variable Width Pulse Train (PWM) This means that the E1538 outputs a continuous train of pulses whose logic 1 pulse width is controlled by the algorithm. The frequency is set by a SCPI command before INIT. Use the following command sequence to set up this mode: SOURce:FUNCtion:PULSe (@) to enable pulse generation. SOURce:PULM[:STATe] ON,(@) to select the PWM mode SOURce:PULSe:PERiod ,(@) to set the pulse repetition period (frequency = 1/).
Variable Frequency Fixed Width Pulse Train (FM) This means that the E1538 outputs a continuous train of pulses whose frequency is controlled by the algorithm. The logic 1 level pulse width is set by a SCPI command before INIT. Use the following command sequence: SOURce:FUNCtion:PULSe (@) to enable pulse generation. SOURce:FM[:STATe] ON,(@) to select the FM mode. SOURce:PULSe:WIDTh ,(@) to pre-set the pulse width of the logic 1 portion of the waveform.
Variable Frequency Square-Wave Pulse Train (FM) This means that the E1538 outputs a continuous train of pulses whose frequency is controlled by the algorithm. The the duty-cycle of the waveform is always 50%. Use the following command sequence: SOURce:FUNCtion:SQUare (@) to enable square-wave generation. SOURce:FM[:STATe] ON,(@) to select the FM mode. The frequency value sent by the algorithm can range from 64Hz to 40KHz. 2 f 4.
Rotationally Positioned Pulse Output This means that the E1538 will generate pulses which are positioned by angle (usually shaft angle). The rotational pulse function requires a rotational reference, and this is provided by the SENS:RVEL function from the SCP’s first channel. There are four related commands that set up rotational pulses. Combinations of these commands can set up four different rotational pulse modes. Figure 20 shows these modes and the command sequence for each.
Rotational Pulse Command Usage Use SOURce:FUNCtion:RPULse (@),(@) to link channels in to the rotational pulse function. The channel in will be linked to the SENS:FUNC:RVEL function to provide the rotational reference information to SOUR:FUNC:RPUL.
Rotational Pulse Mode: Variable Angular Position, Preset Pulse Width (by angle) In this mode, the angular position of the pulses is controlled by the algorithm, and the width (duration in degrees) is preset before INIT. See Figure 21.Use the following command sequence: SOURce:FUNCtion:RPULse (@),(@) to select the channels that will output angular positioned pulses, and to specify the reference channel.
Figure 21. Variable Position, Width Preset by Angle Rotational Pulse Mode: Variable Angular Position, Preset Pulse Width (by time) In this mode, the angular position of the pulses is controlled by the algorithm, and the width (duration in seconds) is preset before INIT. See Figure 22. Use the following command sequence: SOURce:FUNCtion:RPULse (@),(@) to select the channels that will output angular positioned pulses, and to specify the reference channel.
ALG:SCALAR’ALG1’,’Pos3’,300 ALG:UPDATE INIT • • • ALG:SCALAR 'ALG1','Pos1',NewPos1 ALG:SCALAR 'ALG1','Pos2',NewPos2 ALG:SCALAR 'ALG1','Pos3',NewPos3 ALG:UPDATE preset ch 47’s pulse pos to 300° . start algorithm execution calculate values for NewPos(n) later, adjust channel 45’s position while algorithm running later, adjust channel 46’s position while algorithm running later, adjust channel 47’s position while algorithm running values in update queue sent to variables Figure 22.
SOURce:RPULse:POSition[:ANGLe] ,(@), to preset the angular pulse position in degrees. The algorithm will control the pulse duration. SOUR:RPULse:VARType ANGLe,(@) to set the type of value that will vary with algorithm control (in this case pulse width ANGLe).
Figure 23. Fixed Position, Variable Width by Angle Rotational Pulse Mode: Variable Pulse Width (by time), Preset Angular Position In this mode, the pulse duration (in seconds) is controlled by the algorithm, and the angular position is preset before INIT. See Figure 24. Use the following command sequence: SOURce:FUNCtion:RPULse (@),(@) to select the channels that will output angular positioned pulses, and to specify the reference channel.
SOUR:RPULSE:POS:ANGL 140,(@146) preset channel 46 pulse position to 140 degrees SOUR:RPULSE:POS:ANGL 260,(@147) preset channel 47 pulse position to 260 degrees SOUR:RPULSE:VART TIME,(@145:147) algorithm will control pulse duration by TIME Algorithm outputs pulses on all three channels with preset duration. ALG:DEF ’ALG1’,’static float Width1, Width2, Width3;O145 = Width1; O146 = Width2; O147 = Width3;’ ALG:SCALAR’ALG1’,’Width1’,.005 preset ch 45 pulse width to 5ms ALG:SCALAR’ALG1’,’Width2’,.
Stepper Motor Control Use the command SOURce:FUNCtion:STEPper ,,,,(@) to control stepper motors. The E1538 can operate 2 or 4 phase motors in full, and half step mode. Position values are sent from the algorithm to the first channel of a 2 or 4 channel "motor group". The algorithm reads the current position from the second channel of the group. Four-phase stepper motors that require less than 100mA phase current can be directly driven by the SCP.
motor phase channel group can not be split across SCPs. The algorithm sends new position values to the first channel in a motor-group. The algorithm reads the current position value from the second channel in the motor-group.
Figure 27. Full Step Mode, Full and Half Speed, 4-Channel Figure 28.
Figure 29.
*RST and *TST (important!) The *RST and power-on condition (true also after *TST) for outputconfigured channels will output a logical one (open-drain output off). You should keep this behavior in mind when applying the E1415 to your system. It is best to have your system’s digital inputs use a high (one) as their safe state.
SCPI Command Reference Most of the E1538’s commands were available since its introduction. A small number of commands are only available with E1538’s built after February 1998. The following table indicates these new commands with an X in the "for newer units only" column. See "Identifying the Plug-on" on page 5 Table 2.
Table 2.
INPut:POLarity INPut:POLarity , sets logical input polarity on a digital SCP channel. Parameters Parameter Name Parameter Type Range of Values Default Units mode discrete (string) NORMal | INVerted none ch_list string 100 - 163 none • If the channels specified are on an SCP that doesn’t support this function, Comments an error will be generated. See your SCP’s User’s Manual to determine its capabilities.
INPut:THReshold[:LEVel] INPut:THReshold[:LEVel] ,(@) •allows programmatically setting the input threshold level for each input configured channel. Parameters Parameter Name Parameter Type Range of Values Default Units level numeric (float32) -46 VDC to +46 VDC none ch_list string 100 - 163 none • can be set to a resolution of .375V Comments • .
Note Because the E1538 rounds to the nearest multiple of 0.375, the returned value can be different from the value sent. • INP:THR:LEV? returns a numeric value between -46 and +46. The C-SCPI type is float32. • Related Commands: INPut:POLarity, INP:THR:LEVel • *RST Condition: INP:THR:LEV = 1.875 • Send with VXIplug&play Function: hpe14XX_cmdReal64_Q(...
Parameters Parameter Name Parameter Type Range of Values Default Units channel string 100 - 163 none • Channel must specify a single channel Comments • Returned Value: returns one of NORM or INV. The type is string. • Send with VXIplug&play Function: hpe14XX_cmdString_Q(...) [SENSe:]FREQuency:APERture [SENSe:]FREQuency:APERture , sets the time allowed to determine signal frequency and return a reading to the algorithm.
[SENSe:]FREQuency:APERture? [SENSe:]FREQuency:APERture? returns the currently set APERture time. Parameters Parameter Name Parameter Type Range of Values Default Units channel string 100 - 163 none • If the channel specified is on an SCP that doesn’t support this function, Comments an error will be generated. See your SCP’s User’s Manual for its capabilities. • Related Commands: SENS:FREQ:APER • Returned Value: returns numeric aperture in seconds, The type is float32.
exceeds the time-out period (i.e. frequency below LIMit:LOWer), then a frequency of 0 Hz will be returned to the E1415/19/22 algorithm. • Typical use for this command is to allow the user to bound the period of time that is allowed for making a frequency measurement, thus, preventing the SCP from “hanging” during measurement. In this case, typically, the LIMit:LOWer frequency would be the same as, or slower than the frequency associated w/the APERture time.
SENSe:FREQuency:LIMit:LOWer? [SENSe:]FREQuency:LIMit:LOWer? returns the lower frequency limit currently set for Parameters Parameter Name Parameter Type Range of Values Default Units channel string 100 - 163 none • must be a single channel on an E1538A SCP. Comments • Returned Value: .01667 to 250, The type is float32. • Send with VXIplug&play Function: hpe14XX_cmdReal64_Q(...
SENS:FUNC:COND (@144:147) [SENSe:]FUNCtion:FREQuency [SENSe:]FUNCtion:FREQuency sets the SENSe function to frequency for channels in . Also configures the channels specified as digital inputs. See “About Period and Frequency Measurements” on page 16. Parameters Parameter Name Parameter Type Range of Values Default Units ch_list string 100 - 163 none • If the channels specified are on an SCP that doesn’t support this function, Comments an error will be generated.
SENS:PER:MODE • *RST Condition: SENS:FUNC:COND and INP:POL NORM for all digital SCP channels • Send with VXIplug&play Function: hpe14XX_cmd(...) Usage See “About Period and Frequency Measurements” on page 16. SENS:FUNC:PER (@144) [SENSe:]FUNCtion:PWIDth [SENSe:]FUNCtion:PWIDth ,(@) configures channels to measure the input signal pulse width. See “Measure Pulse Width” on page 20.
Parameters Parameter Name Parameter Type Range of Values Default Units preset_count numeric (int32) 0 to 16,777,215 none ch_list string 100 - 163 none Comments • if included, allows presetting the absolute counter associated with the channel pair. All quadrature pairs in will be preset to the same value. If not included, the default count at algorithm start will be zero. • must always specify both channels of a pair. More than one pair can be specified.
Parameters Parameter Name Parameter Type Range of Values Default Units N_teeth numeric (int32) 3 to 255 none index_type string MISSing | EXTRa none ch_list string 100 - 163 none Comments • This function can only be linked to the E1538’s first channel. The function works for wheels that have either a missing, or an extra tooth to mark their index position.
SENSe:]FUNCtion:TOTalize [SENSe:]FUNCtion:TOTalize sets the SENSe function to TOTalize for channels in . See “Totalize Positive or Negative Edge State Changes” on page 15. Parameters Parameter Name Parameter Type Range of Values Default Units ch_list string 100 - 163 none Comments • The totalize function counts rising edges of digital transitions at Frequency/Totalize SCP channels. The counter is 24 bits wide and can count up to 16,777,215.
[SENSe:]PERiod:APERture [SENSe:]PERiod:APERture , sets the time allowed to determine signal period and return a reading to the algorithm. When APERture is large enough to contain more than one signal period, the SCP measures and averages the number of signal periods that will fit within this APERture time. If the specified APERture is less than the input signal period, the SCP stretches the aperture in order to measure at least one signal period. This is known a Adaptive Aperture.
[SENSe:]PERiod:APERture? [SENSe:]PERiod:APERture? returns the currently set APERture time. Parameters Parameter Name Parameter Type Range of Values Default Units channel string 100 - 163 none • If the channel specified is on an SCP that doesn’t support this function, Comments an error will be generated. See your SCP’s User’s Manual for its capabilities. • Related Commands: SENS:PER:APER • Returned Value: returns numeric aperture in seconds, The type is float32.
the LIMit:UPPer period, then a period of 0 sec will be returned to the E1415/19/22 algorithm. (Note: A period value of 0 sec is used as a special token that must be tested for in the user’s provided E1415/19/22 algorithm.) • Typical use for this command is to allow the user to bound the period of time that is allowed for making a period measurement, thus, preventing the SCP from “hanging” during measurement.
[SENSe:]PERiod:LIMit:UPPer? [SENSe:]PERiod:LIMit:UPPer? returns the upper period limit currently set for Parameters Parameter Name Parameter Type Range of Values Default Units channel string 100 - 163 none • must be a single channel on an E1538A SCP. Comments • RETURNS: .004 to 60, Type is float32. SENSe:PERiod:MODE SENSe:PERiod:MODE ,(@) selects the measurement interval mode the SCP will use to measure the signal period.
SENSe:PERiod:MODE? SENSe:PERiod:MODE? (@) returns the measurement interval mode currently set for period measurement. Parameters Parameter Name Parameter Type Range of Values Default Units channel string 100 - 163 none • must be a single channel on an E1538A SCP. Comments • RETURNS: String value "APER" or "NPER", Type is String • .Send with VXIplug&play Function: hpe14XX_cmdString_Q(...
SENSe:PERiod:NPERiods? SENSe:PERiod:NPERiods? (@) returns the number of signal periods the SCP will measure and average to calculate the signal period. Parameters Parameter Name Parameter Type Range of Values Default Units channel string 100 - 163 none • must be single channel on an E1538A SCP. Comments • RETURNS: uint32 value which is the current period count configured. • Related Commands: • *RST condition: SENSe:PERiod:NPERiods SENSe:PERiod:NPERiods = 1 • .
If SENSe:PERiod:RANGe = 1.0 then settings conflict if 1.0sec < APERture < 4.0sec. If SENSe:PERiod:RANGe = 4.0 then settings conflict if 0.01sec <= APERture < 0.04sec The E1415/19/22 driver will report these Settings Conflicts at INITiate time with the following error message: 3129, Incompatible Aperture and Range values,SCP[x] • Related Commands: SENSe:PERiod:NPERiods • *RST Condition: is 1 • .Send with VXIplug&play Function: hpe14XX_cmd(...
is triggered. • If the channels specified are not on a Frequency/Totalize SCP, an error will be generated. • Related Commands: SENS:FUNC:TOT, INPUT:POLARITY • *RST Condition: SENS:TOT:RESET:MODE INIT • Send with VXIplug&play Function: hpe14XX_cmd(...) Usage SENS:TOT:RESET:MODE TRIG,(@134) totalizer at channel 34 resets at each trigger event [SENSe:]TOTalize:RESet:MODE? [SENSe:]TOTalize:RESet:MODE? returns the reset mode for the totalizer channel in .
is ON then the FM state is OFF. If both the FM and the PULM states are OFF then the PULSe channel is in the single pulse mode. • If the channels specified are not on a Frequency/Totalize SCP, an error will be generated. • Use SOURce:FUNCtion[:SHAPe]:SQUare to set FM pulse train to 50% duty cycle.
SOURce:FUNCtion:RPULse SOURce:FUNCtion:RPULse (@),(@) links channels in to the rotational pulse function. The channel in will be linked to the SENS:FUNC:RVEL function to provide the rotational reference information to SOUR:FUNC:RPUL.
these applications. See Figure 30 . Figure 30. For Long Pulses Use Extra Tooth Wheel • Send with VXIplug&play Function: hpe14XX_cmd(...) Usage SENSE:FUNC:RPULSE (@108),(@114,115)reference chan is 108, pulse output on channels 114 and 115 SOURce:FUNCtion[:SHAPe]:CONDition SOURce:FUNCtion[:SHAPe]:CONDition (@) sets the SOURce function to output digital patterns to bits in .
PULM state is enabled then the pulse width modulated mode is active. If both the FM and the PULM states are disabled then the PULSe channel is in the single pulse mode. • Send with VXIplug&play Function: hpe14XX_cmd(...) SOURce:FUNCtion[:SHAPe]:SQUare SOURce:FUNCtion[:SHAPe]:SQUare (@) sets the SOURce function to output a square wave (50% duty cycle) on the channels in .
• is used to select the stepping mode. the allowable values are: Table 3. Stepping values string Stepping Mode Speed Channel MFSFC2 Full Full 2 MFSFC4 Full Full 4 MFSHC2 Full Half 2 MFSHC4 Full Half 4 MHSFC2 Half Full 4 Related error message:3127, "Undefined E1538 Stepper motor mode." • The range of position values that an algorithm can send for the full-speed ("SF") mode is 0 to 65,535.
can be directly driven by the SCP. See Figure 29 for a connection diagram that also shows the required user-supplied output protection components. • specifies the channels that will control stepper motors. The channels referenced can be on more than one E1538. The channels must be in ascending order. Based on the parameter, the channels will be arranged into adjacent groups of 2 ("...C2"), or 4 ("...C4") channels. These groups can not be split across SCPs.
SOURce:PULM:STATe? SOURce:PULM[:STATe]? (@) returns the pulse width modulated mode state for the PULSe channel in . Parameters Parameter Name Parameter Type Range of Values Default Units channel string 100 - 163 none Comments Channel must specify a single channel. • Returned Value: returns 1 (on) or 0 (off). The type is int16. • Send with VXIplug&play Function: hpe14XX_cmdInt32_Q(...
Usage SOUR:PULS:PER .005,(@140) set PWM pulse train to 200 Hz on channel 40 SOURce:PULSe:PERiod? SOURce:PULSe:PERiod? (@) returns the fixed pulse period value on the pulse width modulated pulse channel in . Parameters Parameter Name Parameter Type Range of Values Default Units channel string 100 - 163 none • If the channels specified are not on a Frequency/Totalize SCP, an error Comments will be generated. • Returned Value: numeric period. The type is float32.
• Send with VXIplug&play Function: hpe14XX_cmd(...) Usage SOUR:PULS:WIDTH 2.50E-3,(@143) set fixed pulse width of 2.5 msec on channel 43 SOURce:PULSe:WIDTh? SOURce:PULSe:WIDTh? (@) returns the fixed pulse width value on a frequency modulated pulse channel. Parameters Parameter Name Parameter Type Range of Values Default Units channel string 100 - 163 none • Channel must specify a single channel.
Usage SOUR:RPULSE:POS:ANGL 20,(@145) preset channel 45 pulse position to 20 degrees SOURce:RPULse:POSition[:ANGLe]? SOURce:RPULse:POSition[:ANGLe]? (@) returns the angular position set for , Parameters Parameter Name Parameter Type Range of Values Default Units channel string 100 - 163 none • must specify a single channel only Comments Usage SOUR:RPULSE:POS:ANGL? (@145) return pulse pos set for channel 45 SOUR:RPULse:VARType SOUR:RPULse:VARType ,(@
SOUR:RPULSE:VART TIME,(@143:144) algorithm will control pulse width by TIME SOUR:RPULse:VARType? SOUR:RPULse:VARType? (@) returns the type of value that will be controlled (varied) by the algorithm.
260 degrees SOURce:RPULse:WIDTh[:ANGLe]? SOURce:RPULse:WIDTh[:ANGLe]? (@) returns the width of the rotational output pulse currently set for . Parameters Parameter Name Parameter Type Range of Values Default Units channel string 100 - 163 none • must specify a single channel only.
SOURce:RPULse:WIDTh:TIME? SOURce:RPULse:WIDTh:TIME? (@) returns the width of the rotational output pulse currently set for . Parameters Parameter Name Parameter Type Range of Values Default Units channel string 100 - 163 none Comments Usage 76 • must specify a single channel only.
Specifications These specifications for the E1538A reflect its performance while installed on your VXI module. General Specifications Output Characteristics Input Characteristics (VRS OFF for Chs0&1) Characteristic Pull-Up Off Pull-Up On (10K to Vcc) current source (logic 1) 0 .38mA @ 1.2V current sink (logic 0) 100 mA 100 mA Voltage (logic 1) 0 5V (no load) Voltage (logic 0) 0.5 Max sinking 100mA 0.1 Max sinking 20mA 0.5 Max sinking 100mA 0.
Totalizer Frequency Measurement Period Measurement Capacity 24 bits or 16,777,215 Minimum Pulse Width 500nS Frequency Range 0-100 KHz Gate Time ( taperture ) 1 1 mSec to 1 Second, resolution ----f in Range 1 -------------------- to 100, 000 taperture Accuracy .01% Resolution (Hz) f input ---------------------------------------------------t aperture × 4.
Auto-Gating (adaptive aperture) Rotational Velocity Measure 1mSec to 1Sec for Frequency 1mSec to 1Sec for Perid (using SENS:PER:RANGE 1) 4mSec to 4Sec for Perid (using SENS:PER:RANGE 4) Characteristics Extra Tooth Wheel or Missing Tooth Wheel Range in RPS 100, 000 1 ------------- to --------------------n teeth n teeth Accuracy .01% 2 Resolution in RPS Pulse Width Measure Frequency Source Minimum Pulse Width 500 nS Periods Averaged 1 to 255 Range 5 µS to 1 S Accuracy ±(250nS+0.
Rotational Pulse Source Characteristics Missing Tooth Wheel Position angle range -33.554.430 to 33,554.430 Position resolution 1 degree up to 10,0000 RPS Position width range (angle) 0 to 360 degrees Pulse width resolution (angle) tooth – to – toothangle 238.4nSec the larger of ----------------------------------------------------------- or 360 × --------------------------128 RotPeriod Pulse width range (time) 0 to Rotational Period (see note 3 on page 65) Pulse width resolution (time) 238.
