Ni pci-6602 PFI pins and io register configuration

Hello, I am a new user of pci-6602 board and I am using matlab xPC. I would like to use some PFI pins as digital output. I am not sure about what to do after configuration I/O Register. I configured I/O Register for inputs and outputs. Then which register should i use for sending data? SW Save register or else? And do i have to do anything with I/O Window registers? This not clear in manual. I need help in this issue.
Thanks

Hi bckr,
There is additional examples and documentation available with the NI Measurement Hardware Driver Development Kit. This includes example code and links to the documentation.
I would advise posting any questions you have after that to the Driver Development Kit forums. This is where you will find people actively supporting register level programming with the 660x boards.
It looks like you use GO_Load_A_Registers.writeGO_Load_A command to load the register after initializing the MITE board.
If you have any further questions then please post them to the Driver Development Kit forum, that is where you will receive the best support.
Have a great evening,
MatthewW
Applications Engineer
National Instruments

Similar Messages

How can I Save and Load the Configuration File of a VNA HP8510C with LabView

Hello, I'm working with a HP8510C. In order to simplfy the use, I try to save and to load the configuration file. Actually, such files are saved in the HP8510C, but there is only 4 places to save. It will be more interresting when I can storage this file in the computer with Labview. I don't have found anything about in the Documentation.
Has someone already deal with such a question?
Géraud DEVOS
IWE Karlsruhe

geraudIWE a écrit:
Hello, I'm working with a HP8510C. In order to simplfy the use, I try to save and to load the configuration file. Actually, such files are saved in the HP8510C, but there is only 4 places to save. It will be more interresting when I can storage this file in the computer with Labview. I don't have found anything about in the Documentation.
Has someone already deal with such a question?
Géraud DEVOS
IWE Karlsruhe
Hello GerauIWE,
Have you try to use the Hewlett-Packard 8510C Instrument Driver?
You can download it on :
http://sine.ni.com/apps/we/niid_web_display.drv_results?p_app_area=&p_man=hewlettPackard&p_keywords=8510c&p_inst_type=&p_env=845&p_drv_type=&p_int=
Best Regards,
Sanaa T
National Instruments France
Sanaa T.
National Instruments France
#adMrkt{text-align: center;font-size:11px; font-weight: bold;} #adMrkt a {text-decoration: none;} #adMrkt a:hover{font-size: 9px;} #adMrkt a span{display: none;} #adMrkt a:hover span{display: block;}
>> http://www.nidays.fr/images/081110_ban_nidays09_468X60.gif

PCI 6602:How can I use the digital lines of the board and in the same time to generate pulse train using a counter?

Hello!
My problem appeared when I tried to update my code from Traditional NI-DAQ Legacy to DAQmx.
I am using 2 counters (counter 5 and counter 7) from PCI-6602, to generate pulse train, and also the Digital I/O lines of the port 0 (the lines form 0 to 7). What I do in my application is that I am starting to generate the pulse train on the output of the 2 counters, and after that I am playing with the state of the digital lines.
In traditional there was no problem using the counters and the digital lines in the same time, everything was going perfectly, but in DAQmx this is not possible.
What happens: I start to generate pulse train on the output of the counters, no errors encountered, but when I try to modify the state of one line of the digital port the generation of the pulse train is stopped. This is happening when I start the task associated to the digital port.
My question is: it is possible to create a channel on the digital lines without altered the channels created for the counters?
Another thing what I manage to see using the "Measurement & Automation Explorer" and Test panels for PCI-6602, basically is the same thing, I generate pulse train on the output of the counter 7 and try to start a task on the digital line, but I get one error :
"Error -200022 occurred at Test Panel
Possible Reason(s):
Measurements: Resource requested by this task has already been reserved by a different task.
Device: Dev4
Terminal: PFI8"
Instead if I use the counter 0 or counter 1 to generate pulse train I don't encounter the same problem.
Which resources are used by the counters 2 to 7 from the PCI-6602 board and the counters 0 and 1 do not use?
Thank in advance for any replies!
Ciprian
Solved!
Go to Solution.

Hello Jordan, thank you for your reply.
I am sorry but I can not see or run your example, I don't use LabView, I use Visual C++ for developing.
Here is the code for generating the pulse train:
GeneratePulseTrain(unsigned long ulCount1, unsigned long ulCount2)
    short nStatus = 0;
    nStatus = DAQmxCreateTask("",&m_taskHandle);
    nStatus = DAQmxCreateCOPulseChanTicks (m_taskHandle, "Dev4/count5", "", NULL, DAQmx_Val_Low, 0.0, ulCount1,ulCount2);
    if( bTriggerMode == true) // if hardware trigger is enabled
       nStatus = DAQmxSetTrigAttribute (m_taskHandle, DAQmx_ArmStartTrig_Type, DAQmx_Val_DigEdge);
       nStatus = DAQmxSetTrigAttribute (m_taskHandle, DAQmx_DigEdge_ArmStartTrig_Edge, DAQmx_Val_Rising);
       nStatus = DAQmxSetTrigAttribute (m_taskHandle, DAQmx_DigEdge_ArmStartTrig_Src,"Dev4/PFI17" );
   //set the internal timebase
   nStatus = DAQmxSetCOCtrTimebaseSrc(m_taskHandle,"Dev4/count5","20MHzTimeBase" );
   nStatus = DAQmxStartTask(m_taskHandle);
    return nStatus;
And the code where I try to set the digital line:
SetChannelState(short nState)
    short nStatus = 0;
    uInt8 wrtBuf0[1]={0};
    nStatus = DAQmxCreateTask("",&m_taskHandle);
    // Configure line as output
    nStatus = DAQmxCreateDOChan (m_taskHandle, "Dev4/port0/line0", "", DAQmx_Val_ChanPerLine);
nStatus = DAQmxStartTask(m_taskHandle);
    wrtBuf0[0] = nState;
    nStatus =DAQmxWriteDigitalLines (m_taskHandle, 1, 0, 0, DAQmx_Val_GroupByScanNumber , wrtBuf0, NULL, NULL);
    nStatus = DAQmxWaitUntilTaskDone(m_taskHandle,10);
    nStatus = DAQmxStopTask(m_taskHandle);
    nStatus = DAQmxClearTask(m_taskHandle);
    m_taskHandle = 0;
    return nStatus;

Sharing an external sample clock between PCI-6722 and PCI-6602

I need PCI-6602 work with PCI-6722。6602 shares 6722’s ao/SampleClock as external clock and triggered by 6722’s ao/StartTrigger。The master device is 6722, which refered as Dev1, and the slave device is 6602, which refered as Dev2. A RTSI line is used to connect the two devices correctly.
I use C API to finish my program and my code is as follows:
//config 6722 analog out task
1、DAQmxCreateTask("NI6672", &hAOTask);
2、DAQmxCreateAOVoltageChan(hAOTask, "Dev1/ao0", "", -10.0, 10.0, DAQmx_Val_Volts, "" );
3、DAQmxCfgSampClkTiming(hAOTask, "", 1000.0, DAQmx_Val_Rising, DAQmx_Val_ContSamps, 1000);
4、DAQmxWriteAnalogF64(hAOTask, 1000, 0, 10.0, DAQmx_Val_GroupByChannel, data, NULL, NULL);
//config 6602 counter task
5、DAQmxCreateTask("NI6602", &hCounterTask);
6、DAQmxCreateCICountEdgesChan(hCounterTask, "Dev2/ctr0", "", DAQmx_Val_Rising, 0, DAQmx_Val_CountUp);
//use /Dev1/ao/SampleClock for external clock
7、DAQmxCfgSampClkTiming(hCounterTask, "/Dev1/ao/SampleClock", 1000.0, DAQmx_Val_Rising, DAQmx_Val_ContSamps, 1000);
//use /Dev1/ao/StartTrigger
8、DAQmxSetTrigAttribute (hCounterTask, DAQmx_ArmStartTrig_Type, DAQmx_Val_DigEdge);
9、DAQmxSetTrigAttribute (hCounterTask, DAQmx_DigEdge_ArmStartTrig_Src, "/Dev1/ao/StartTrigger");
10、DAQmxSetTrigAttribute (hCounterTask, DAQmx_DigEdge_ArmStartTrig_Edge, DAQmx_Val_Rising);
//start counter task first
11、DAQmxStartTask(hCounterTask);
//start 6722 task
12、DAQmxStartTask(hAOTask);
I run it on the MAX virtual Device, and the Step 11always returned -89120。
I try to slove this problem, so I change the Step 7, use /Dev2/PFI9 to instead of /Dev1/ao/SampleClock.
7、DAQmxCfgSampClkTiming(hCounterTask, "/Dev2/PFI9", 1000.0, DAQmx_Val_Rising, DAQmx_Val_ContSamps, 1000);
The code runs well, but I don’t know which terminal is connected by /Dev2/PFI9. Does it connect to /Dev1/ao/SampleClock？
I use another API DAQmxConnectTerms to ensure that, I add a Step before Step 11.
DAQmxConnectTerms( "/Dev1/ao/SampleClock", "/Dev2/PFI9", DAQmx_Val_DoNotInvertPolarity );
The program also run well. But I am still not sure that 6602 is sharing /Dev1/ao/SampleClock。If not, which terminal of Dev1 is connected by /Dev2/PFI9?
Is my code right? If not, hwo to fix my code or supply some example for me? Thanks.

Hello Shokey,
From looking over your post, it looks like you want to program in C, using simulated instruments, a master/slave design with a PCI-6602 and PCI-6722. The PCI-6722 is the master device and the PCI-6602 is the slave device. In order to implement this with the real cards, you would need a RTSI cable between the 2 cards in order to pass the triggers and the sample clock. Unfortunately with simulated devices you can't implement this so parts of your code won't be able to work exactly like if you had the instrument.
If you did have the instrument, you can implement this by performing the following steps:
Master Device:
1.) Export the ao/SampleClock and ao/StartTrigger to a RTSI Line. (See DAQmx C Reference help for DAQmxExportSignal to export these)
Slave Device:
1.) Set the Sample clock and the trigger to the RTSI.
There is another forum that I think will help you out to implement this correctly. In this forum, the customer was trying to export a trigger through a RTSI and the problem he was experiencing was a broken RTSI cable. His code, he states, works. I hope this helps you with this and if you have any more questions, feel free to post.
Jim St
National Instruments
RF Product Support Engineer

Error -200141 when doing buffered events with DAQmx and PCI-6602

When doing buffered events with DAQmx and PCI-6602 I get error 200141 - Data was overwritten before it could be read by the system.
This error is generated ONLY with random inputs >200/sec.
My setup is :
DAQmxCreateCIVCountEdges(taskhandle,"Dev1/ctr3"....
DAQmxCG+FGSampClkTiming(taskhandle,"/Dev1/FPI35",...
DAQmxSetCICountEgdesChan(taskhandlem,"", "/Dev1/80MHZTimeBase")
DAQmxSetChanAttribute(taskhandlw,",",DAQmx_CI_DataXferMech,DAQmx_Val_DMA,0);
Can somebody help ?

i'm getting the same Error-200141, while reading semiperiods. (Meas_Buffered semiperiod continous)
while loop ex.rate seems to be pulsewidth*no.Samples to read. in my case PW=60ms
Input buffer size measured with Property node= 10000
why this error happens?? i cant use any mode other than implicit timing for semi-period measurement right??
more info: all the ai channels are used ~ 16 differencial.
i found one solution which is _ reinitializing the whole task if an error occur. is this the right way??
Kudos always welcome for helpful posts
Attachments:
Counter_1_Meas Buffered Semi-Period-Continuous_main_lv09.vi ‏34 KB
SemiPeriod_Reconnect Counter on Error.vi ‏35 KB

Synchronize PCI- 5421 and PCI-6602

I am using a PCI 6602 to generate four pulse trains. I am also generating a signal with a PCI 5421 AWG. All signals are started at the same time by using a common start trigger. The problem I am having is that after they run for a while the 6602 and 5421 signal start drifting. I know in the past I had sync clocks in a PXI chassis but I am unsure how to syncronize the clocks using PCI card. I do have an RTSI cable linking the cards together so could someone please give me an example of how to sycronize these cards in Labview (8.2)

Hello Kiebach,
You seem to be connecting the signal correctly in your NI-DAQmx program. However, I do not see any NI-FGEN code where you import the signal to be used as an external clock. Have you added this code? I think you would benefit from examining the example program entitled "niFgen_DAQmx_Synchronization_Example.vi". This program shows how to synchronize an NI-DAQmx device and an SMC Arb device. You can find the example by opening the NI Example Finder utility; you can open this utility from LabVIEW by going to the Help menu and selecting Find Examples... Once you have opened the NI Example Finder, you can navigate to this example by selecting the Browse tab and going to Hardware Input and Output>>Modular Instruments>>NI-FGEN (Signal Generators)>>Synchronization. You will notice that this example uses the Export Signals VI rather than the Connect Terminals VI. To help understand the difference between these two, you may want to examine this document.
Matt Anderson
Hardware Services Marketing Manager
National Instruments

I can't register my PIN and IME (HELP PLEASE)

I really need your help guys, I bought a Blackberry 8520 from black market. It's brandnew because it sealed and complete with accesories. The seller told me that the unit was free from Sun Cellular and was sell to him buy the previous owner. The unit is already openline/unlocked already. I'm using a smart sim card but when I tried to register my unit to https://smart.blackberry.com I got an error that my unit is suspended or deactivated. I can use Wifi via hotspot browser but when I tried to use a facebook or twitter application I got an error "Your are currenty on the data plan service, contact your service provider to upgrade your data plan". I think the previous owner (which I don't know) is not paying his bill. Now I contact suncellular and as per them when the owner not paid their bills they only block the sim card and not the phone. As per them it might be the blackberry is blocking my connectivity. How can I register my PIN again? My phone is total useless.
Unit: 8520 Curve
Blackberry Tech and Admin I need your Help

csabillo18 wrote:
I want to subscribe to Smart BIS but during the registration of my pin and IMEI my phone is suspended or deactivated. Now how can I register my phone from other carrier if my phone pin is suspended or deactivated. SUN cannot help me about it.
You can't. Once the device PIN/IMEI has been suspended or deactivated, it can't be removed. You've probably purchased a stolen as lost BlackBerry, as stated above. Only the original carrier who suspended the PIN and can remove it, you would need to contact them.
You need to get your money back from the seller, obviously they lied to you.
1. If any post helps you please click the below the post(s) that helped you.
2. Please resolve your thread by marking the post "Solution?" which solved it for you!
3. Install free BlackBerry Protect today for backups of contacts and data.
4. Guide to Unlocking your BlackBerry & Unlock Codes
Join our BBM Channels (Beta)
BlackBerry Support Forums Channel
PIN: C0001B7B4 Display/Scan Bar Code
Knowledge Base Updates
PIN: C0005A9AA Display/Scan Bar Code

PCI-6602, How to convert Pulse Width to RPM and stop updating datalogging at 30 RPM

Hi all,
My objective is to stop updating data logging pulse width measurements at 30 RPM so I can record the time lenght it takes the RPMs to stop from 6000 to 30 RPM. When I turn off the tool. I have an encoder attached to an output shat of a 6000 RPM circular saw. I have created 3 program methods, but I was not able to stop at 30 RPM. The last pulse width value the data log updates is around 200 RPM. I don't know if I'm using the right method to read RPMs?
System:
1)     NI-PCI 6602 Counter/Timer Card
2)     SBC-60 Connector Block
3)     TRD-S1000-VD Encoder. 1000 PPR
4)     LabVIEW 8.5.1
5)     PC Dell Precision T3400 (32-bit), Intel Core Quad 2.4GHz, Memory 2GB. Windows XP prof.
In method 1: I reading pulse width and converted to RPM with this formula. RPM = 60/(1000 PPR/ Pulse Width).
In method 2: I just measuring pulse width and try to stop while loop when pulse width value is greater than 0.002 mSec. by using this formula 60sec/30rpm = 2 sec/rev, 1 Rev = 1000 counts. Therefore,     2 Sec / 1000 Counts = 2 mSec/Cnt (0.002)
In method 3: I measuring pulse width using this formula,                                                                   Pulse Width (in Sec) = Count/Counter Timebase Rate (20MHz), One period is 1000 cnts X 0.002mSec = 2. Therefore, Pulse Width = 2 / 20MGz = 0.000000100
All three methods stop recording pulses around 200 rpm. I wonder if the formulas I utilizing, are not using them properly. Or there is floating point number conversion???? Please See attached Picture.
Any help is greatly appreciated. THANKS!!!
Carlos G.

Charles_DeJesus,
Could you check the output waveform of the encoder? Do you see spikes? Sometimes spikes might produce wrong counts.
CarmenC

Connect NI PCI-6602 with NI PCI-6503

Hello,
I want to connect a NI PCI-6602 Counter/Timer with the NI PCI-6503 DIO-Card. The problem is the varying number of pins. (6602->68 pins; 6503 -> 50 pins). Is there a possibility to connect both? Maybe a complete adapter?
regards Thomas

Thomas,
You are correct both cards have male connectors. You could still use the 68M-50F connector if you use a 68-68 cable. Or if you had a 68F-50M then you would need a 50 pin cable. I have found another option, the R6850-D1 Cable(part number 777419-01) . This is a digital cable that was made to use our 68 pin digital devices with 50 pin breakout boxes. It ties the ground lines together and you also loose access to PFI 37,the up/down pin for counter 0, and you loose the +5V line. I think you may want to check the pin mappings to make sure that you really want to connect these 2 boards directly together. When using a 50 pin conversion with the 6602 you will get the following pin mapping:
Pin Number (1-50) 6602 Signal Name
1 PFI_25
2 PFI_28
3 PFI_27
4 PFI_24
5 PFI_30
6 PFI_31
7 PFI_26
8 PFI_29
9 PFI_21
10 PFI_23
11 PFI_19
12 PFI_17
13 PFI_18
14 PFI_16
15 PFI_22
16 PFI_20
17 GND
18 PFI_34
19 GND
20 PFI_35
21 GND
22 PFI_33
23 GND
24 PFI_32
25 GND
26 GND
27 PFI_38
28 GND
29 Reserved
30 GND
31 PFI_36
32 GND
33 PFI_39
34 GND
35 PFI_4
36 PFI_6
37 PFI_0
38 PFI_2
39 PFI_1
40 PFI_3
41 PFI_7
42 PFI_5
43 PFI_13
44 PFI_10
45 PFI_15
46 PFI_14
47 PFI_8
48 PFI_11
49 PFI_12
50 PFI_9
You will loose half of the cards functionality since half the pins (even numbered pins) will be connected to ground on the 6503. It would be easy for you to short lines to ground this way. It would probably be better if you get a breakout box for each card (SCB-50 and SCB-68) and then connect only the lines you want to share between the cards. So in answer to your question, yes you CAN connect then directly together, but do so with caution, and I do not feel this direct connection is the best solution for y
ou.
Hope this helps.
Kevin R

Pci 6602 external clock

Hello I'm a little bit a newb concerning the PCI-6602, and I need somenones help. I have a APD which delivers signals I want to count while an external gate is high. My code so far (this is just pseudo code since I have a wrapper in python): I have connected the signal I want to count to the PFI39 and the Gate to Gate - ctr7
DAQmxCreateTask('', task)
DAQmxCreateCIPulseWidthChan( task, "/dev1/ctr7", '', 0, MaxCounts*DutyCycle/f, DAQmx_Val_Ticks, DAQmx_Val_Rising)
DAQmxSetCIPulseWidthTerm( task, "/dev1/ctr7", "" )
DAQmxSetCICtrTimebaseSrc( task, "/dev1/ctr7", "/Dev1/PFI39" ) )
DAQmxSetCIDupCountPrevent(task, "/dev1/ctr7", True )
DAQmxSetReadRelativeTo(task DAQmx_Val_CurrReadPos) )
DAQmxCfgImplicitTiming( task, DAQmx_Val_FiniteSamps, 1000)
DAQmxSetReadOffset(task, 0)
DAQmxSetReadOverWrite(task, DAQmx_Val_DoNotOverwriteUnreadSamps)
DAQmxStartTask(task)
DAQmxReadCounterU32(task
, 1000
, 0.008
, 285099872
, 1000
, ctypes.byref(self._CINread), None)
DAQmxStopTask(task)
this is not actual code, this is just copied from a python file - thus not C Synthax, but the functions should be ok.
If I set the Gate to low however I still get counts, although the Gate is low. Can anyone help me? Did I connect the gate / src to the correct pins?

The behavior you describe doesn't make sense to me. Having configured implicit timing, you would only expect a single sample every time the gate signal goes from high to low. Each buffered sample would indicate the number of source ticks that occurred between sequential rising and falling edges of the gate signal. Is this the behavior that you intended? If the gate is just staying low one would expect the read call to timeout since no new samples would be available.
Does DAQmxSetCIPulseWidthTerm( task, "/dev1/ctr7", "" ) not return an error? On my simulated 6602 as well as my real PCIe-6351 I get error -200254 indicating that an empty string is not a valid terminal (although I know for a fact that this does work for counter output terminals, I don't think it makes much sense for the input terminal on a pulse width task). In any case, you should just specify the PFI line to which you have connected your gate signal.
Best Regards,
John Passiak

660x select PFI pin number.vi

Hello,
I have recently installed LabView 7 + Device Drivers, DAQmx 9.5.1, and T-DAQ 7.4.4, on Windows XP-32bit OS. I have 2 PCI 6602 and a PCI 16E-4 cards plugged in.
All devices have been detected properly in MAX.
I tried to execute an old code written in LabView 6.1 (Win2k), but I get an error saying "660x select PFI pin number.vi : subVI is missing".
Can anyone please help me out? Where can I find this subVI?
Any help is greatly appreciated. Thanks.

Hi nithyan,
When upgrading to a new version of LabVIEW it's sometimes possible that old code isn't 100% compatible with the new version. It may be that LabVIEW 7 doesn't utilize the 660x Select PFI Pin Number.vi. If that is the case you may have to recode that part of your program.
You could also try checking in the C:\Program Files\National Instruments\LabVIEW x.x directory to see if the VI is there.

Conceptual problem in using a PCI-6602?

Hi, All You Wild and Crazy NI/LabVIEW Types --
I have a problem that's been close to sending me off the deep end for more than a month now, and I think that I'm so enmeshed in it that I can't see the forest for the trees anymore. I'd like to apologize in advance for the length of this post, but there are some details that might or might not be important, and I'd rather make the mistake of giving you too much information than not enough.
We do impact-cratering experiments, using a gun to launch (usually) spherical projectiles at a variety of targets. One of our big efforts is to measure the velocities at which material is ejected from growing craters. We do that with a line-generating laser, oriented so the "sheet" of laser light is perpendicular to the target's surface and through the impact point; we strobe the laser at a programmed rate (with our PCI-6259 board) and take a time exposure of the scene with a Nikon D100 DSLR. When target material -- usually grains of sand -- is ejected, the laser illuminates a "slice" through the curtain of ejecta, illuminating a small portion of the fragments numerous times in their trajectories. Since we know the scale of the photograph and its orientation relative to the laser's illumination, and we also know the rate at which the laser is flashing, we can easily calculate the velocities of the illuminated particles. I'm attaching a picture (file 4044, cropped.jpg) of an example taken with an older camera to give you an idea. In the picture, the laser's illuminating the scene from the right of the frame and the projectile flew into the picture from the top of the frame, traveling along the left-hand edge. The brightest portion is the flash from the impact, and the rest of the parabolic trajectories are the grains of sand in flight. The target bucket, full of coarse sand, is the elliptical looking cylinder at the bottom of the picture. It's roughly 28 cm in outside diameter, if you'd like a scale.
As you might imagine, with our projectiles moving anywhere between 0.7 and 3 km/s, sequencing everything is pretty important. We're using (or trying to use) LabVIEW to do all of the sequencing, instrument control, and data storage. Things are going pretty well so far, except for what I'll describe in more detail below. A couple more things, though, first. It's important that we measure the projectile's speed in each shot, as that controls impact energy and momentum, which are critical to know in a given experiment. We do that with simple laser-photodetector pairs (which we normally call "velocity stations") arranged along the projectile's trajectory. As the projectile passes between a laser and its detector, its shadow is detected and a TTL pulse is sent to our PCI-6602 board. Depending on the experiment, we use three or four such laser-dector pairs. They use counters 0, 1, 2, and 3. We know the distances between the laser stations and, once we get the times between detections, it's s simple matter to calculate the projectile's velocity.
We also use LabVIEW to fire the gun, and we do that because opening the camera's shutter has to be synchronized with the firing pulse, which currently is sent via P1.1 on the 6259. Here's the problem: when we test the laser-detector arrays in a "standalone" mode (that is, without any other tasks or operations being done with LabVIEW), they work infallibly. It's when we try to use LabVIEW to fire the gun that we get either very erratic results from the velocity stations/6602 or no results at all.
I've tried a range of things, from starting the two-edge measurement task before the firing signal is sent, to trying to force things with a timed sequence, to doing things with brute force via a seuqence structure. When I try to start the two-edge measurement task first, though, the firing signal isn't sent until the counters time out. This of course, wrecks the experiment, because all of the timing is then messed up. The VI that I've attached (Version 1.vi) is a HIGHLY simplified version of the initial attempt I made at doing this, with all sorts of background stuff removed just so I can cut to the chase. (Only one two-edge measurement task is shown, for instance.) I think that the VI is pretty self-explanatory (and embarrassingly primitive), so it probably doesn't need much in the way of explanation. Counter 7 and PFI 0 on the 6602 are used to accept the signal from the firing button and trigger the event structure, which contains the two-edge separation and gun-firing tasks. (In reality, I use a separate VI to have three to four concurrent two-edge separation tasks running concurrently, one for each velocity station.) I start the two-edge separation tasks first so the detectors and counters are ready for the projectile. It's not necessary here, but I kept the 500 ms wait frame in this example because that's why the sequence structure exists -- to allow the shutter of the Nikon to open completely before the gun fires. After those 500 ms, the firing signal is sent to the circuit that actually fires the gun.
What happens in this configuration is that the second frame of the sequence structure doesn't execute until the 5-s timeout transpires in the two-edge separation task. I've also tried this using a line on the 6602 to fire the gun instead of P0.1 on the 6259, but that ends up with the same result. (Both counters are used on the 6259 to strobe the main illumination laser, so they're unavailable, if you're wondering. In any case, we need four counters for the four velocity stations.)
FINALLY, my question: What am I doing wrong, here? If I put the two-edge separation tasks in the same frame of the sequence structure as the firing task, the gun fires when it's supposed to, but we get no velocity measurements. I've also tried to force the timing with another version of a sequence structure; I'm attaching another very simplified version below as Fire and speed example.vi.
After you recover from your violent fits of laughter, I'd really appreciate hearing what you might recommend. (And no, surrender isn't an option.)
Thanks for taking all of your valuable time to read this huge post -- I really appreciate it!
Mark
Attachments:
4044, cropped.jpg ‏197 KB
Version 1.vi ‏35 KB
Fire and speed example.vi ‏30 KB

I agree with all 3 of Kevin's points. His first suggestion will probably fix your problem (see below). The 2nd and 3rd suggestion would improve efficiency and responsiveness, but #2 might not be possible since independently triggering four outputs in hardware would require the use of 4 counters (on the 6602 anyway) which might be busy doing other tasks in your application (although if you don't need the stations to trigger independently then you could implement this with a single counter).
I think I have an explanation of the problematic behavior you are seeing based off of the following bits of information from your post:
1. Running the small example code by itself works flawlessly, but adding other simultaneous functionality fails. You mentioned you are doing this on 4 stations, so I'm assuming 4 counter input tasks running in parallel.
2. The behavior you are seeing is that the 2nd sequence does not execute until after the read times out (note that the sequence is supposed to be executing in parallel with the read).
It sounds like the problem is coming from a combination of calling into DAQmx Read before data is available (this consumes one of the threads that LabVIEW has allocated to your application until DAQmx Read finishes executing) along with the fact that LabVIEW allocates 4 threads per execution system per priority by default. Since all of your threads (from what I can tell) are executing on the same priority, the 4 reads you are calling will block anything else from executing until they have completed. By then it's too late and the firing of your gun happens after the counter task has already timed out.
You *may* increase the number of threads allocated to your application by using a VI that is included with LabVIEW (vi.lib\Utility\sysinfo.llb\threadconfig.vi) and this would also probably remedy the behavior you are seeing. However, rather than throwing more threads at this application I think the better solution would be to change the sequencing of your tasks like Kevin suggested ("create and start the 2-edge task before entering the sequence structure, and defer the 2-edge *reading* until *after* firing the DO")--in doing this you would now expect to see data immediately upon calling DAQmx Read and you avoid the situation where Read is blocking indefinitely and consuming an application thread. You could take this a step further by checking the Available Samples per Channel property (or using the DAQmx EveryNSamplesAcquiredIntoBuffer event) to ensure that data is actually available before calling Read.
Best Regards,
John Passiak

How to generate a pulse on x number of events PCI-6602

I am running LabVIEW 5.1 full development with a PCI-6602 counter board.
I would like to generate an output pulse after counting x number of input pulses. I would also like to reset the counter with an external signal.
My application is I am trying to generate a second index pulse for an encoder.
I would like to count the pulses from encoder phase A and generate an output pulse on x number of counts. Then I would like to reset the counter using the encoder’s index pulse. This way I can change the phase of the “generated” index pulse with respect to the “real” index pulse by x number of counts (degrees) and maintain that regardless of encoder rpm.
Thanks
Brian

Brian,
There actually is a way to do what you want, but it gets a little complicated. I don't have LV on this machine so I'll have to just describe the idea. First a summary: the counter will repeatedly countdown to 0. Each time it reaches 0, it will generate a brief pulse which will in turn hw-reset the counter value to N. Then it will countdown to 0 again, etc. The same brief pulse could also be wired to a different encoder-measuring counter to create a "delayed" reset to 0 (or some other #).
1. Configure your counter for "position measurement" instead of "simple event counting". Set the encoder type to, um, I forget the name -- something like "two pulse encoder." It's the setting that will increment with every SOURCE edge and decrement with every AUX edge. Wire your encoder channel A to the counter's default AUX input (in position encoder mode, you must use the default input pins). Hard wire from the default SOURCE input to GND. Now every encoder edge will decrement the count, and nothing wlil ever increment it.
2. Configure the counter to use z-indexing. Set the z-index reload value to be N-1, where N is the # of encoder counts by which to delay the encoder's real z-index pulse. Set the z-index reload phase appropriately, probably to A low B low. Wire the real z-index pulse to the counter's GATE input.
3. Configure the counter to "pulse on terminal count" -- you do this using 'Counter Set Attribute.vi'. So N encoder edges after the real z-index pulse, you'll generate a pseudo-z-index with this counter.
4. You can wire this pseudo-z-index to the GATE input of the encoder-measuring counter. Now the encoder's z-index pulse is delayed by an amount you can program.
5. Note: this method requires the motion to be uni-directional.
Good luck!
-Kevin P.

Count digital events on a Counter with pci-6602 with callback on CVI

Hi,
I'm using a PCI-6602 card with CVI 8.5 and I need to trig on event.
On every pulse I received, I need to do some actions like increasing a counter, send a message on Rs232 etc.. I don't want to do any loop checking that the counter value has changed. I would like to use a callback to execute this code only on the edge or counter value event.
My problem is that I don't know which function can do this. Is there any way to get an event on a pci-6602?
Thanks
James
Solved!
Go to Solution.

Hello.
It's completely possible to create a callback that will allow you to do what you want when a edge will occur on an external signal you define.
To do this, you can for exemple create a counting edges task that will use one of the 6602 counters,and the set your external signal to be the source of your sample clock.You'll then be able to register a callback with the function DAQmxRegisterSignalEvent, and your callback will be called each time an edge will occur on your specified sample clock source.
Here's 2 links that explain the events in DAQmx and how to handle them in CVI. The example ReadDigChan-ChangeDetectionEvent.pr that ships with DAQmx examples (Hardware Input and Output<<DAQmx<<Digital measurements) can be very useful to understand how to do. This example creates a signal event callback to detect change detection for digital inputs.
Regards.

6602 Save Registers and FIFO

Hello,
I've been searching through the forums and noticed that their are many oppinions concerning the size of the onboard memory buffer for the PCI-6602 board. Some say the board has a 1 or 2 sample buffer (FIFO) while others say the board has a 16 sample FIFO. I was hoping someone could clear this up for me.
Lets assume that we are running a buffered event counting measurement using DMA transfers. What I understand from the register level programming manual is that the counter has two save registers (Gi HW, and Gi SW). When a gate signal latches the counters count, it places it into one of these registers. The next count would be placed into the second save register. My understanding is that the DMA transfer, sends the data in the save registers directly to the internal buffer configured by the user on the computer running the DAQ software. This would mean that the save registers on the card are the FIFO buffer that everyone talks about, and thus the card only has a 2 sample buffers because each counter only has 2 save registers which each hold only one 32bit number. Is this correct?
If it is not, then what happens? If it is correct, then where did this idea of a 16 sample FIFO buffer come from?
Thank you for your help,
Matt
Attachments:
NI 660x Register level Programmer Manual.pdf ‏868 KB

Hello Matt,
You are correct each counter has 2 sample FIFO and here
is the data flow.
Counter register -> 2 Sample FIFO on 6602 ->
Transferred across PCI Bus using DMA -> RAM Buffer -> Read by software
I did see the forum post which says about 16 FIFO for a
TIO board, but could not find any documentation on that. Apart from that here is the knowledgebasethat talks about the buffer size of 660x boards.
Thanks
nAyer

Ni pci-6602 PFI pins and io register configurat​ion

Similar Messages

Maybe you are looking for

Ni pci-6602 PFI pins and io register configuration