Counter Output with NI cDAQ 9188

I am trying to generate pulses with the counters included in the NI 9188 cDAQ chassis.
I tried first to do that with NI 9411 module but this task didn't figure out in MAX.
I'm trying now to perform that with the PFI 0 BNC connexion in the chassis but that still doesn't exist in max
what should I do?

Duplicate Post
Best Regards,
John Passiak

Similar Messages

Do I have to use an external clock with a cDAQ-9188 and NI 9401 to read a linear encoder? I'm seeing error message that implies that but the example code doesn't show it.

We can set up a task that works on demand but when we go to continuous sampleing we see Error -200303, which claims an external sample clock source must be specified for this application. However, some of the NI linear encoder example code doesn't show that (uses the cDAQ 80 Mhz clock) and the documentation didn't mention that.

It's mentioned in the 918x user manual:
Unlike analog input, analog output, digital input, and digital output, the cDAQ chassis counters do not have the ability to divide down a timebase to produce an internal counter sample clock. For sample clocked operations, an external signal must be provided to supply a clock source. The source can be any of the following signals:
AI Sample Clock
AI Start Trigger
AI Reference Trigger
AO Sample Clock
DI Sample Clock
DI Start Trigger
DO Sample Clock
CTR n Internal Output
Freq Out
PFI
Change Detection Event
Analog Comparison Event
Assuming you have at least one available counter (there are 4 on the backplane), I would suggest to configure a continuous counter output task and use its internal output as the sample clock. Specify the internal counter using an "_" for example "cDAQ1/_ctr0". The terminal to use for the sample clock source would be for example "/cDAQ1/Ctr0InternalOutput".
Which example uses the 80 MHz timebase as a sample clock? It is far too fast for a sample clock on the 9188 according to the throughput benchmarks (80 MHz * 4 byte samples = 320 MB/s). There is also no direct route between the 80 MHz timebase and the sample clock terminal for the counters--making this route would use a second counter anyway.
Best Regards,
John Passiak

Two counter outputs with 90deg phaseshift

Hi,
I have NI PXI-1042 chassis and two NI PXI-6513 digital output cards in it.
Task is to create two pulses with 90degrees phaseshift.
Is there function in labview 7.1 which generates pulses descriped above. I`m meaning that if I tell function to count up, signal A is ahead signal B and if A is 90 degrees behind B it means counting down?
Is there way to do this by connecting 3 (signal A, signal B and GND) counter wires all in one counter and controlling only one counter to "count output down" or "Count output up"?
- Santtu

Hi Santtu,
I think I understand what you are trying to do.
Essentially you have two counters, but you want to be able to control their
phase relationship to one another. This is definitely possible to do;
however, there are not many examples dealing with it.
I did find one Traditional DAQ Example (non- M-Series) that
might help you out with this: Twin
Pulse Train Generation with Variable Phase Shift Control
Traditional DAQ uses an older API, so I would recommend you look at the
attached example over this example. Just wanted to give you more
than one option.
As far as it 'counting' up or down, that really would have
to be done by a counter input task. Since the input would be the same as
that for a quadrature encoder, then you would use the methods described in my
previous post. As the output it will simply look like two different
counters.
For the best solution though, I went ahead and created an
example for you. It shows how to generate 2 different counter pulses that
are out of phase with one another by a specified amount of time.
Hope this helps,
Otis
Training and Certification
Product Support Engineer
National Instruments
Attachments:
Gen Dig Pulse Train-Continuous-Dig Start-Phase Shift.vi ‏82 KB

Counter Input with Delayed counter Output with board 6023E

HELLO
Is possible with board 6023e have two counters working at same time in this case i need a counter to creat a delay and another one to read. If isn´t possible how i can have a delay in microseconds.

Yes, each one of those boards have two STC counters you can use. Take a look at the User Manual of the boards for more information. When looking at the pin diagram for the boards, the counter pins are GPCTRx_.
If you are using LabVIEW, CVI, VB or VC++, when you install NI-DAQ, it will install a lot of counter example programs which will show you how to program the counters.
Brian

Different Counter Outputs with different number of samples

I´m using an 6602 Timing I/O Board and/or a MIO 6281. For timing control of our measurements I use different counters from both boards triggered by a Digital Out for synchronization. The counters are set to CO Pulse Time, implicit timing, digital triggered and finite sample mode.
Lets assume I use two Ctr´s from the 6602 board. My problem is when setting the number of samples from only one CTR to another value then the second I´m getting an error. The rest works perfect, I can use different starting delays, low or high times, only different sample amounts don´t work. It´s regardless if I use the Timing I/O or Multi I/O board.
For example:
Ctr 0 / 6602 _ _ | |_ _| |_ _ --> 2 samples
Ctr 1 / 6602 _ _ | |_ _
Somebody any idea or advice?
Solved!
Go to Solution.

Here is my currently used code, perhalps it helps you understanding the problem. Both are doing the same but one is a bit optimized. Hopefully someone can help.
Attachments:
Example_1.png ‏70 KB
Example_2.png ‏90 KB

Can I generate pulse trains on more than one counter output at the same time?

I have a PCI 6601 card with a BNC 2121 to connect the signals to two devices. The card is used as a trigger for both devices and I want to be able to generate pulse trains on two output channels at the same time, with a time delay between the two. How do I do that in Labview 7.1 Development with DAQmx?

I feel foolish for not being able to figure this out, but it still doesn't work. Attached is the VI I use now. Counter 0 generates a finite pulse train and I programmed Counter 1 to generate a retriggerable single pulse triggered by CtrOinternaloutput. I still get the same error message: -50103 The specified resource is reserved. The operation could not be completed as specified.
The same happens if I set the trigger for counter 1 at PFI36 (default output of counter 0) or any other PFI line. If I try a pulse train generation on only one of the counters, both work fine.
If I try the example in traditional DAQ for multiple counter outputs with phase delay, it works fine.
Can you tell me what I'm doing wrong?
Attachments:
Shutter_AND_lamp_trigger.vi ‏103 KB

How to Immediately Change Counter Output Rate?

I have a piece of code that largely works like this example: http://zone.ni.com/devzone/cda/epd/p/id/5493
In other words, I set up the Counter Output with some initial frequency and duty cycle, but then during the main loop of my program I continuously change the frequency to a new value based on other criteria.
I'm using an M-series PXI card and LabVIEW RT.
The problem I'm having is that the card waits for the next edge before changing the counter output rate. For instance, lets say it is going at a low frequency and I am upping to a high frequency. If the command arrives in the middle of the current pulse, it will wait to complete the low-rate pulse before starting the high frequency output. Is there a way to make it interrupt the current count and immediately start counting at the new rate?
Thanks,
Isaac

Hi Isaac,
I posted the code in LV 8.2 so you should be able to open it now (it sometimes takes several minutes to upload).
There are a few limitations to using the digital lines instead of the counters:
1. The digital lines are updated off of a sample clock which will be much slower than a timebase. For example, on the 6221 the maximum update rate is 1 MHz, while the counter output has a max timebase of 80 MHz. As a result, the number of frequencies you can generate are going to be more restricted (divide down from 1 MHz vs. 80 MHz).
2. On M series devices, the digital lines must be clocked from an external source. This could be generated from a counter
3. You have to build the digital waveform, which is a bit tricky (I think the example code should help out with that but I haven't had time to thoroughly test it).
4. If you are generating digital lines at fast rates, you will need to write quite a few samples at a time to the output buffer to ensure the data does not underflow. If the buffer includes multiple periods of the digital signal, you would have the case that using the counter output would still update more immediately.
Again, to determine the best course of action it would be useful to know what frequencies you want to generate and which exact hardware you are using. I just mentioned the digital lines as an alternative to the counters, but it might not be ideal for your situation.
-John
John Passiak

How to use counter output pulses to trigger analog input?

Hello all,
I hope the kind people using this forum can help me, a lowly beginner LV programmer! I have been attempting to create a VI that produces a user defined number of TTL pulses, separated by every n seconds. Each TTL would be outputted to a stimulator, which in turn generates its own TTL. Using the stimulator-generated TTL, I would like to trigger finite analog data acquisition (e.g. for every TTL, trigger the collection of a data sweep that contains 4000 samples (collected at 4000 Hz), with 1000 samples collected pre-trigger. I would like to also be able to see each data sweep as it is triggered on a chart. As I understand things (lots of online/book/forum reading), I should be using the counter output to generate my TTL pulses, and syncing each counter produced TTL with analog input, as well as using a reference trigger. Also, the AI part should be started first, so that I don' t miss any counter outputs. If it matters, I also need to use one of the AI channels to acquire the TTL, so I can see my stimulator-induced responses to the stimulator in time.
I am able to generate the TTL pulses from the counter output, but I am having a problem with the AI part. I am unsure how to sync the counter output with AI. Also, since I need to acquire pre-trigger samples, I would be needing to acquire samples continuously, but when I set 'continuous samples' on daqmx timing, the VI doesn't work (hence why's its set to 'finite samples').
I hope someone out there can help, as I have been at this for what seems ages, with limited success. I am using a USB-6259 and LabView v8.2. Thanks!
Attachments:
RC001 v_1.vi ‏49 KB

Hello,
Due to the fact that analog tasks themselves are not retriggerable, a
pulse train produced by a counter is always used as the sample clock
for the analog input task in order to recreate a retriggerable effect
for analog input. This can be done by creating a finite pulse train set
to retriggerable using the DAQmx Trigger Property Node, or the pulse
train could be continuous and just be gated by another signal. Neither
of these methods can be properly applied in hardware to create a
retriggerable reference trigger. You can however implement something
similar in software by just stopping and restarting your reference
triggered analog input task within a loop. There will be some delay
between when the task is stopped and restarted, as these events require
software intervention, but if there is enough time between when each
trigger signal is generated, there should not be any noticeable delay
or missed samples.
I have attached an example of this!
Mark B
===If this fixes your problem, mark as solution!===
Attachments:
RC001 v_1mod.vi ‏25 KB

DAQmx: 2 Counter Outputs in 1 Task?

Is it possible to have two counter outputs with different timings in one task?
One counter will be used to generate a PWM pulse train and the other one will be used to re-arm the trigger for analog data acquisition.
Thanks for your help.

Hi,
Thank you for posting to the NI forums. You should be able to output on two counters with separate timing sources. I’ve done just this using an M Series DAQ device and the DAQ Assistant’s auto-generated LabVIEW code. The screenshot to this VI is attached below.
I hope this helps. Please post back if you have further questions.
Ed W.
Applications Engineer
National Instruments
Message Edited by Ed W on 01-26-2007 01:50 PM
Message Edited by Ed W on 01-26-2007 01:50 PM
Message Edited by Ed W on 01-26-2007 01:51 PM
Attachments:
Two Counters.JPG ‏56 KB

Buffered counter output in C

Hi everyone,
I am looking for a possibility to generate a finite buffered counter output with varying pulse widths, using the X-Series. I am working in C / Python.
I want to output two pulses triggered to an external signal. The first pulse should be short, the second pulse long.
The following code outputs only two identical pulses. How can I modify it to output two different pulses?
CreateCOPulseChanTicks(channel,"","100MhzTimebase",DAQmx_Val_Low,0,300,300)
CfgImplicitTiming(DAQmx_Val_FiniteSamps,2) #output two pulses
CfgDigEdgeStartTrig(src,DAQmx_Val_Falling) #external signal
SetStartTrigRetriggerable(True) #retrigger
Best Regards,
Stefan

It's good you found a workaround but the behavior doesn't seem right to me...
The default behavior in DAQmx (the C / LabVIEW / .NET APIs) is to regenerate data from the buffer. Perhaps the python wrapper you are using is disallowing regeneration somewhere? I tried this with regeneration disabled and it gives the same behavior you reported (though with regeneration enabled it does not).
You can use DAQmxGetWriteRegenMode to verify this theory and DAQmxSetWriteRegenMode to enable regeneration in case it is disabled.
Best Regards,
John Passiak

SignalExpress 2012 does not recognize cDAQ-9188

How can I setup SignalExpress to communicate with the cDAQ-9188 module? I found the system in MAX but I can see no device connected in the Channel View.

Hi Runner,
I saw there is nothing in your channel view, could you please check the version of your NI-DAQmx driver from Control Panel>>Uninstall a program>>National Instruments Software?
Here is my channel view:
And here is the version of NI-DAQmx:
You can download the latest DAQmx driver here: http://sine.ni.com/psp/app/doc/p/id/psp-268

Please help with C code to synchronize counter output to analog input

Hi All,
I am using NI DAQ USB-6353 with text-based C code to control it. I would like to send a continuous pulse train from the DAQ to pulse a power supply, which then activates an electron beam producing current to be read by the analog input port of the same DAQ. I would like to keep only the analog samples during the pulse peak and samples of a couple pulse widths right after. I am successfully to generate a pulse train using the sampled clock from a counter output channel, but fail to use the same clock to synchronize the pulse train with the analog input. DAQmxReadAnalogF64 is not called by the static function EveryNCallback set for the analog input task. Am I doing something wrong with the following codes? It would be great if it turns out only I am using the wrong sampled clock name of the counter ("dev1/PFI8") for the analog input. Or is something more fundamental that a counter cannot be sync. with an analog input?
Would someone be able to send me a link to an example in C or C++ or visual basic showing how to synchronize a buffered sample clocked digital pulse train from a counter output channel to an analog input? To simplify the post, the below codes do not include the static functions EveryNCallback and DoneCallBack, but I can send them if needed.
Many thanks in advance for your help,
Thuc Bui
//setting operation parameters
double initDelay = 0.0, freq = 10;
double dutyCycle = 0.0001;           //thus pulse width is 10 microsec
unsigned highTicks = 4;   //per period
unsigned numSamplesPerPeriod = highTicks / dutyCycle; //40000 samples/period
unsigned lowTicks = numSamplesPerPeriod - highTicks;      //per period
unsigned sampleRate = 2*numSamplesPerPeriod*freq;       //800000 samples/s
//create counter
TaskHandle counterTask;
int errCode = DAQmxCreateTask("", & counterTask);
errCode = DAQmxCreateCOPulseChanFreq(counterTask, "dev1/ctr0", "",
                                 DAQmx_Val_Hz, DAQmx_Val_Low,
                                 initDelay, freq, dutyCycle);
errCode = DAQmxCfgSampClkTiming(counterTask, "dev1/PFI8", sampleRate, DAQmx_Val_Rising,
                           DAQmx_Val_ContSamp, numSamplesPerPeriod);
//create analog input
TaskHandle aiTask;
double minVolt = 0.0, maxVolt = 1.0;
errCode = DAQmxCreateAIVoltageChan(aiTask, "dev1/ai0", "", DAQmx_Val_Diff,
                                 minVolt, maxVolt, DAQmx_Val_Volts, "");
unsigned bufferSize = 10* numSamplesPerPeriod;
errCode = DAQmxSetBufInputBufSize(aiTask, bufferSize);
errCode = DAQmxCfgSampClkTiming(aiTask, "dev1/PFI8", sampleRate, DAQmx_Val_Rising, DAQmx_Val_ContSamp, numSamplesPerPeriod);
errCode = DAQmxRegisterEveryNSamplesEvent(aiTask, DAQmx_Val_Acquired_Into_Buffer,
                                        numSamplesPerPeriod, 0, EveryNCallback, 0);
errCode = DAQmxRegisterDoneEvent(aiTask, 0, DoneCallBack, 0)
//start aiTask first
errCode = DAQmxStartTask(aiTask);
//then counterTask
errCode = DAQmxStartTask(counterTask);

Hi Xavier,
Thank you very much for getting back to me. I really appreciate it. I followed your advice with the option 2 and simplified my code by using one of the NI C example templates to generate the below codes (also attached). I was able to see the pulses generated with an oscilloscope, and on the same oscilloscope I could see the ouput pulses of the electron beam probe. Unfortunately, the below code via DAQmxReadAnalogF64 reports of no data read from the probe and finally times out. Below is the error message given by this function. I did check the connection of the analog input wires to make sure they were connected to pin 1 (A0+) and 2 (A0-) because I was using the terminal configuration DAQmx_Val_Diff. Do you see any obvious errors I have made in my codes?
Thanks a lot for your help,
Thuc Bui
Task started, waiting for trigger...
Acquired 0 analog samples DAQmx Error: Some or all of the samples requested have not yet been acquired.
To wait for the samples to become available use a longer read timeout or read later in your program. To make the samples available sooner, increase the sample rate. If your task uses a start trigger, make sure that your start trigger is configured correctly. It is also possible that you configured the task for external timing, and no clock was supplied. If this is the case, supply an external clock.
Property: DAQmx_Read_RelativeTo
Corresponding Value: DAQmx_Val_CurrReadPos
Property: DAQmx_Read_Offset
Corresponding Value: 0
Task Name: _unnamedTask<1>
Status Code: -200284
End of program, press Enter key to quit
********************** C Code **************************************************
#include <stdio.h>
#include "NIDAQmx.h"
#include <math.h>
#define DAQmxErrChk(functionCall) { if( DAQmxFailed(error=(functionCall)) ) { goto Error; } }
int main(void) {
int32 error = 0;
char errBuff[2048]={'\0'};
TaskHandle taskHandleDig=0;
TaskHandle taskHandleAna=0;
double  timeout=10;
double minVol = -1.0, maxVol = 1.0;
double initDelay = 0.0;
double freq = 10.0;
double pulseWidth = 1.0e-5; //10us
double dutyCycle = pulseWidth * freq;
unsigned hiTicks = 4;
double sampleRate = hiTicks/pulseWidth; //samples/s
unsigned lowTicks = ceil(sampleRate/freq) - hiTicks;
unsigned nSpPeriod = hiTicks + lowTicks;
unsigned numPulses = 1;
unsigned nSpCh = numPulses*nSpPeriod;
double sampleRate2 = ceil(2.0*sampleRate);
unsigned sampleMode = DAQmx_Val_FiniteSamps;
/*********************************************/ /*/ DAQmx Configure Code /*********************************************/
DAQmxErrChk(DAQmxCreateTask("", &taskHandleDig)); DAQmxErrChk(DAQmxCreateTask("", &taskHandleAna));
DAQmxErrChk(DAQmxCreateAIVoltageChan(taskHandleAna, "Dev2/ai0", "", DAQmx_Val_Diff, minVol, maxVol, DAQmx_Val_Volts, ""));
DAQmxErrChk(DAQmxCfgSampClkTiming(taskHandleAna, "/Dev2/Ctr0InternalOutput", sampleRate2, DAQmx_Val_Rising, sampleMode, nSpCh));
DAQmxErrChk(DAQmxCreateCOPulseChanFreq(taskHandleDig, "Dev2/ctr0", "", DAQmx_Val_Hz, DAQmx_Val_Low, initDelay, freq, dutyCycle));
DAQmxErrChk(DAQmxCfgSampClkTiming(taskHandleDig, "/Dev2/PFI12", sampleRate2, DAQmx_Val_Rising, sampleMode, nSpCh));
unsigned bufferSize = nSpCh;
DAQmxErrChk(DAQmxSetBufInputBufSize(taskHandleAna, bufferSize));
DAQmxErrChk(DAQmxSetBufOutputBufSize(taskHandleDig, bufferSize));
/*********************************************/ /*/ DAQmx Write Code /*********************************************/
DAQmxErrChk(DAQmxWriteCtrTicksScalar(taskHandleDig, 0, timeout, hiTicks, lowTicks, NULL));
/*********************************************/ /*/ DAQmx Start Code /*********************************************/
DAQmxErrChk(DAQmxStartTask(taskHandleAna)); DAQmxErrChk(DAQmxStartTask(taskHandleDig));
printf("Task started, waiting for trigger...\n");
/*********************************************/ /*/ DAQmx Read Code /*********************************************/
double* dataAna = new double[nSpCh];
int32 numReadAna = 0;
int errCode = DAQmxReadAnalogF64(taskHandleAna, -1, timeout, DAQmx_Val_GroupByChannel, dataAna, nSpCh, &numReadAna, NULL);
printf("Acquired %d analog samples\n",numReadAna);
if (numReadAna) {
    unsigned nPts = (numReadAna < hiTicks)? numReadAna : hiTicks;
   for (unsigned n = 0; n < nPts; ++n) {
         printf("%6.3f ", dataAna[n]);
    printf("\n");
delete [] dataAna;
DAQmxErrChk(errCode);
Error:
if( DAQmxFailed(error) )   DAQmxGetExtendedErrorInfo(errBuff,2048);
if( taskHandleDig!=0 && taskHandleAna!=0 ) {
/*********************************************/   /*/ DAQmx Stop Code   /*********************************************/
    DAQmxStopTask(taskHandleDig);
    DAQmxClearTask(taskHandleDig);
    DAQmxStopTask(taskHandleAna);
    DAQmxClearTask(taskHandleAna);
if( DAQmxFailed(error) )   printf("DAQmx Error: %s\n",errBuff);
printf("End of program, press Enter key to quit\n");
getchar();
return 0;
Attachments:
Correlated DIO AI_Sample_Clock Dig Start.c ‏6 KB

Counter output becomes unsnchronized when gated with an other counter

Dear all
i'm using a PCI-6602 to generate a range of different pulse trains / retriggered pulses. Ctr0 is running at the experiments base frequency (T0) and is configured like this:
Error = DAQmxCreateCOPulseChanTicks(T0TaskHandle, "Dev1/ctr0", "", "20MHzTimebase", DAQmx_Val_Low, 0, T0Low, T0High);
Error = DAQmxCfgImplicitTiming(T0TaskHandle, DAQmx_Val_ContSamps, 0);
A second counter (Ctr2) produces pulses synchronized with T0 but with n times longer period:
Error = DAQmxCreateCOPulseChanTicks(BlockTaskHandle, "Dev1/ctr2", "", "20MHzTimebase", DAQmx_Val_High, 0, BlockLow, BlockHigh);
Error = DAQmxCfgImplicitTiming(BlockTaskHandle, DAQmx_Val_ContSamps, 0);
Error = DAQmxCfgDigEdgeStartTrig(BlockTaskHandle, "/Dev1/Ctr0InternalOutput", DAQmx_Val_Rising);
A third counter (Ctr3) produces retriggered pulses from Ctr2 that will serve as a gate for the 4th counter output:
Error = DAQmxCreateCOPulseChanTicks(BlockEnableTaskHandle, "Dev1/ctr3", "", "20MHzTimebase", DAQmx_Val_Low, 0, BlockEnableLow, BlockEnableHigh);
Error = DAQmxCfgDigEdgeStartTrig(BlockEnableTaskHandle, "/Dev1/Ctr2InternalOutput", DAQmx_Val_Rising);
Error = DAQmxCfgImplicitTiming(BlockEnableTaskHandle, DAQmx_Val_FiniteSamps, 1);
Error = DAQmxSetStartTrigRetriggerable(BlockEnableTaskHandle, true);
Ctr4 should now output pulses at the frequency of Ctr0 but only when Ctr3Out is high. I tried along the lines of:
Error = DAQmxCreateCOPulseChanTicks(TriggerTaskHandle, "Dev1/ctr4", "", "20MHzTimebase", DAQmx_Val_Low, 0, TriggerLow, TriggerHigh);
Error = DAQmxCfgImplicitTiming(TriggerTaskHandle, DAQmx_Val_ContSamps, 0);
Error = DAQmxSetPauseTrigType(TriggerTaskHandle, DAQmx_Val_DigLvl);
Error = DAQmxSetDigLvlPauseTrigWhen(TriggerTaskHandle, DAQmx_Val_Low);
Error = DAQmxSetDigLvlPauseTrigSrc(TriggerTaskHandle, "/Dev1/Ctr3InternalOutput");
This works in terms of gating, but the gated pulses are no longer synchronized with the Ctr0 (they "move" through the gate when looking at it on an oscilloscope).
DAQmxCfgDigEdgeStartTrig does not work for Ctr4 as it is not possible to use start and pause in the same task (at least that's what the error message said).
I tried to synchronize using:
Error = DAQmxSetArmStartTrigType(TriggerTaskHandle, DAQmx_Val_DigEdge);
Error = DAQmxSetDigEdgeArmStartTrigSrc(TriggerTaskHandle, "/Dev1/Ctr0InternalOutput");
Error = DAQmxSetDigEdgeArmStartTrigEdge(TriggerTaskHandle, DAQmx_Val_Rising);
which works if i uncomment the three PauseTrig lines (no more drifting pulses, but no gating either). Using it all together produces no errors but the gated pulses still walk through the gating window.
Any help is deeply appreciated
Best regards
Christian

Hello Wolfgang
thank you for your reply. I finally managed to get the 6602 to do what i want it to. The key was to use
Error = DAQmxSetDigEdgeArmStartTrigSrc(TriggerTaskHandle, "/Dev1/Ctr2InternalOutput");
instead of
Error = DAQmxSetDigEdgeArmStartTrigSrc(TriggerTaskHandle, "/Dev1/Ctr0InternalOutput");
and to make sure that Ctr4s task was started after the tasks of Ctr0 and Ctr2.
Now Counter 4 is pulsing at the frequency of Ctr0 (even with selectable delay and pulse width) but only when Ctr3Out is high without the need for an external AND gate or other hardware.
Best regards
Christian

Two counter inputs and counter output NI 9401

I am trying to configure two counter inputs and one counter output on one NI 9401. I have looked and found how to configure digital lines in booth directions but it seems like I can only do two counters in all on one module. Can someone verify this for me or let me know how to get all three on to one module?
Thank you

Hi mschoenwald,
The counters are actually located on the backplane of whatever chassis you are using--I'll assume you are using cDAQ and not cRIO.
If you have the older <link no longer exists>, then there are only 2 counters available in general. You can access both from a single parallel (8 lines or less) digital module in slot 5 or 6 of the chassis.
The 2nd generation Compact DAQ chassis (including 9174, 9178, 9181, 9188, etc.) includes 4 counters. You may access them from any slot with a parallel module. There is no restriction preventing you from accessing all 4 simultaneously from a single module.
The 9401 is bi-directional and configurable by nibble (line0:3 may be configured one direction, and line4:7 another). However, it is quirky in that it requires the line direction to be configured before any of the tasks are started. This is because the data lines themselves are used to set the line direction behind the scenes. The best way to work around the behavior is to use DAQmx Control Task to explicitly reserve your tasks before any of them are started (see here). Keep in mind that the counter output should use the opposite nibble from the two counter input tasks.
Best Regards,
John Passiak

Châssis cDAQ-9188, accès aux propriétés des cartes d' E/S

Bonjour,
J’ai un châssis cDAQ-9188 avec 4 cartes d'entrées sorties
     - NI 9425
     - NI 9411
     - NI 9472
     - NI 9263
Avec le logiciel Measurement & Automation Explorer,
je ne parviens pas à accéder aux propriétés de ces cartes, pouvez-vous
m'aider ?
Vianney Leroux

Hi,
And thank you for posting
here. Please post in english on this english forum. If you want, you have a
French community on this link:
French community
I translate your post for
the others users.
Vianney has a cDAQ-9188
with 4 input/output modules:
- NI 9425
- NI 9411
- NI 9472
- NI 9263
With MAX, she can’t access
to propriety of her modules.
If I understand, you can
see the modules but the tab propriety is grey tin. If so, it is normal. The access
to the propriety tab depends of your module (only specific one).
Why do you want access to
propriety?
What do you want configure?
Regards,
Samuel G.
Samuel G. | Application Engineer Team Leader
Certified LabVIEW Developer
National Instruments France
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Counter Output with NI cDAQ 9188

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