Gated-event counting using analog triggers?

I'd like to software trigger gated-event counting with analog signals. eg. Use a comparison to check analog input levels to a 6024E card, once a trigger level is reached send a digital out from the 6024E to a 6601 gate to commence and terminate a counter of the 6601 card.
I have found that the counter on the 6024E card is not stable enough for this application, but the NI-TIO cards work reliably.
Any tips greatly appreciated,
Alan

Alan;
In case you want to trigger a finite pulse train generation of an analog hardware trigger, you can still accomplish that with an e-series board only.
You will need to use both general purpose counters available on the DAQ device though. The first counter needs to be configured as retriggerable pulse generation, having its gate being routed to the AI Start Trigger pulse of the Analog Input task. With that done, the counter will generate a pulse at its output at every time the Analog Trigger level is met. You, then, configure the second counter to execute a continuous pulse train and route the first counter output to the second counter gate input. That will make the second counter to generate a pulse train that will be "enabled" by the first counter. The p
ulse train will be generated while the output of the first counter is on its high state level.
Knowing that, you can configure the pulse width of the first counter to be as wide as you need the second counter to generate the pulse train.
Hope this helps.
Filipe A.
Applications Engineer
National Instruments

Similar Messages

Gated event counting for a finite time

I am using a PCI 6110 card for gated photon counting. The digital signal is coming from a single photon counting module, which generates a single TTL pulse upon receiving a photon. It also generates ~100 dark count /sec. To get rid of the dark counts, I use gate pulses with very small duty cycle. In this way, the dark counts are suppressed. I want to operate for a fixed time interal with a resolution of ~1ms. My gate pulses are at 800kHz. Their duration is on the order of 10ns. Is there a way that I can perform gated counting for only 10000 gate pulses? Thanks.

Hi UMeng,
Your question stirred up an interesting discussion at the office. You can't do gated, buffered counting as the gate input is used to trigger the latch to the buffer. We came up with a couple of ideas here, but neither are perfect. It is important to also consider that you are running right at the specifed minimum pulse durations for the gate and source pulse durations for the 6110, which is 10 ns.
NI PCI-6110/6111 Specifications
http://digital.ni.com/manuals.nsf/websearch/A9694D34EF10469386256E3000539747
With that in mind, you could use an external high speed AND gate to generate a signal for a simple event counter to read using the laser gate and the photon detector output as input to the AND gate.
Otherwise, you could try doing gated event counting on the signal and simple event counting on the gate as long as the gate frequency is consistent. Then you could use the frequency of the gate and number of counts of the gate to get the total acquisition time. This will require that you start and stop both counter tasks at as close to the same time as possible. The start could be triggered with an Arm Trigger. Getting the values from the counters would always require 2 software calls, but the longer the acquisition, the less important this error would become.
Let me know if either of these sound appealing.
Regards,
John Bongaarts
AE Specialist - Test Products

Gated event counting on 6602

I am trying to use gated event counting or single pulse width measurement techniques to count TTL pulses on two counters during an external gate pulse. The problem is that if zero TTL pulses (a possible condition) go to both counters during the gate, the "armed" attribute does not seem to change from "yes" to "no", allowing the vi to kick out of a while loop and read the value that the counter stored.
Is there a way of setting up the counters so that
1) both counters only collect counts during an external gate
2) zero counts are allowed
3) the counters change state from "armed" to "not armed" at the end of the gate pulse regardless of whether there were TTL pulses on the source channel during the gate?
Thanks,
-Martin

Based on your description of the application, I assume that you are using traditional DAQ. If you have an application where you sometimes expect to have zero source pulses between gates, you should enable synchronous counting (ND_COUNTING_SYNCHRONOUS) (referred to as "duplicate count prevention" in DAQmx). Many of the examples in traditional daq have this as an option that can be enabled on the front panel.
I hope this helps!
gus....

Event counter using USB-6210 analog

Hi,
Any suggestions or directions where to look to generate a VI that would record event from a magnetic counter of a mouse wheel. I would like to record up to 16 wheels using the USB-6210 device. Thanks!
VO2max

Thanks for the extra information.
The 6210 actually has two counters, so you could count the edges (on two of the wheels) if the signals are TTL compatible. You can use the Count Digital Events.vi example to help you get started. From LabVIEW, it can be found at:
Help » Find Examples... » Hardware Input and Output » DAQmx » Counter Measurements » Count Digital Events
If your signals are TTL compatible, I would highly recommend purchasing a PCI-6602 and using this method for all 8 channels. You could modify the example code by increasing the delay (software-timed sample rate) to a larger value (say 1 minute), and logging the results to a file as you run. Doing this would log the value of the event counter every minute, and would keep the file size relatively small (about 15kB if you run for 8 hours).
If you must use a single 6210 and require all 8 channels, the only option would be to use continuous analog inputs. You would have to sample at a high enough rate to not skip the pulses (I am not sure what that is without knowing more about the signal), and then process the digitized signal in software to determine the information that you need. I would use the Producer/Consumer design template in conjunction with a continuous analog input example to get started. In the consumer loop, you would have to implement the functionality of the counter in software.
Using a hardware counter would be preferrable to using analog inputs. The counter is made for exactly this type of task, and implementing it in software can be complicated as well as processor intensive. If you have any questions let me know, I'm happy to help you out. You can always try out the counter task on the 6210 for two wheels to see how it will work before deciding whether or not to purchase a new board.
-John
P.S. After your first post I had assumed that you were testing computer peripherals, but it looks like you actually have eight rodents. We had a good laugh over here over my confusion.
John Passiak

How to use analog Triggering and External clock scan

Hi, there. I want to measure the engine cylinder pressure with an PXI6070-E card and BEI encoder. I have tried using Cont Acq&Graph ExtScanClk D-Trig.vi and Cont Acq&Graph ExtScanClk Soft A-Trig.vi , but they don't work. What I did was to connect a 50HZ pulse to PFI0 (analog triggering, I changed the code from digital triggering to analog triggering), and a 100K pulse to PFI7 (startscan), and an 50 HZ analog signal to ACH0. But the code always says: timeout. If I use internal clock, it works fine. Could you please give me some help? THANKS A LOT!

Hey Wyuan,
I tested the Cont Acq&Graph ExtScanClk Soft A-Trig.vi and it worked fine. However, the Cont Acq&Graph ExtScanClk D-Trig.vi has a small error in its logic that will prevent the data from ever being displayed to the graph. In order to run the examples you need to connect a trigger to pin 11 and a scan clock to pin 38. A 10kHz square wave would be fine for the clock signal and just a single pulse would work for the digital trigger.
One additional think to keep in mind is the grounding. You might need to connect you ground from your signals to a DGND pin. I am including the two programs that I used for the test.
I hope this helps,
Joshua
Attachments:
Cont_Acq&Graph_ExtScanClk_D-Trig.vi ‏121 KB
Cont_Acq&Graph_ExtScanClk_Soft_A-Trig.vi ‏153 KB

I am having trouble using analog triggering on PFI0 with PCI-6110

I am having trouble with analog triggering. I am trying to use PFI0 as an anlog input for triggering purposes and this is on a PCI-6110 card. I am outputing a 10Hz 5Vpp triangle wave signal from an analog output channel and inputing it into PFI0. I am configuring the trigger with the code listed at the bottom. When I start the data acquisition is not triggered. If I increase the frequency up to about 480-500Hz then the trigger will start and then I can actually move the frequency back to 10Hz and it will continue to trigger. Also if I leave the code the same and the waveform the same but switch the trigger type to cwaiHWdigital then it will trigger at the 10Hz level. I suspect that this may have something to do with the coupling of the PFI0 input but I am not sure if this is the case and if it is I do not know how to configure the coupling of PFI0 in measurement studio VB. Any thoughts would be appreciated.
cwaiDAQ2.StartCondition.Source = "PFI0"
cwaiDAQ2.StopCondition.Type = cwaiContinuous
cwaiDAQ2.StartCondition.Type = cwaiHWAnalog
cwaiDAQ2.StartCondition.Mode = cwaiFalling
cwaiDAQ2.StartCondition.Level = 2
cwaiDAQ2.Configure
cwaiDAQ2.Start

I tried increasing the voltage and this did not seem to have nay affect on the frequency that it started triggering. I also tried to lower the trigger level. As far as trying other PFI's I dont believe I can. As fas as I can tell PFI0 is the only one that can be used as an analog input and analog trigger.
I looked at the article in the knowledge base 2ZD9B3W3 and it seems to be a similar problem. I tried to replicate the code in my program but I really have no experience with NI_DAQ function calls in visual basic so maybe I am doing it incorrectly. I did not get any errors but the NI_DAQ function calls are mixed in with CWAI measurement studio function calls so maybe when I configure cwai it resets what I have just changed with NI_DAQ. I could really use some specific direction on how to succesfully set PFI0 to DC coupling with the CWAI control or how to mix measurement studio and NI_DAQ functions.

I'm trying to use DAQmx for simple event counting using PFI8

Hi,
I am presently using Traditional DAQ (Legacy) drivers in my software, however I'm in the process of switching over to DAQmx drivers. Our systems use an E Series DAQ card: PCI-MIO-16XE-10.
I use PFI8 along with Counter 0 to do simple event counting. The signal is connected to PFI8 and as it changes, my counter output either increase or decreases in value. The attached vi shows how I've done it in the past using the Legacy drivers (top portion of the vi) and how I'm attempting to do it using the DAQmx drivers. I've combined both versions on the single vi just for illustration purposes - when I do my testing they are on separate vi's.
I'd appreciate it if anyone could help me to figure out why my DAQmx version isn't working properly. Thank you very much!
Steve
Attachments:
PFI8_DAQ_Comparison.vi ‏36 KB

Hey Steve,
The DAQmx driver installs several examples into LabVIEW that
demonstrate how to implement various event counting applications. I
recommend you look over these and see if any of them accomplish what
you're trying to do. They're usually very simple to understand and
well documented, but I'd be happy to help you out with any of them if
you had a particular question.
You can find them in the Example Finder (Help >> Find Examples)
in LabVIEW. Drill down to the following location in the directories:
Hardware Input and Output >> DAQmx >> Counter Measurements >> Count Digital Events
You'll see a number of examples, but I recommend starting with 'Count Digital Events.vi'
Since PFI8 corresponds to CTR0 SRC, make sure you set it to use counter 0. This should work correctly.
Elijah Kerry
Senior Product Manager, LabVIEW
Follow my Software Engineering for LabVIEW Blog

How do i develop code in LabVIEW 7.1 for configuring and performing gated edge counting using NI-DAQmx

Hi,
My application requires DAQ counter channel to count the rising edge of the input signal connected to the source pin of the counter. This counting has to take place only when there is a high pulse in gate pin of the same counter.This can be developed easily using traditional daq vis.
Please let me know how to develop code using DAQ mx.
Thanks,
Sudha

There is an example that demontrates how to do this in DAQmx called "Count Digital Events-Pause Trig.vi".
gus....

Encoder edge counter using analog input

I have using an 9215A USB (4AI).
2 AI are logging data in to a txt-file and the other 2AI will be used for counting the edges from a quadrature encoder (A and B pulse train).
Every edge falling or rising I will write a line in the txt-file also show a egde counter in the VI (total edges read).
I'm a beginner so I need some help to find out how to do.
BR
Johan

the 9215A do 20kSam/s , that not too much, so .... your encoder should change state 10k/s max.
first approach: continious read (with max speed) with two buffers, while one buffer is filled by the DAQ, analyse the data of the other. Three independend loops : first wait for and read buffer-> send data via queue to second analyse loop -> send data via second queue to third loop that does the file handling.
second approach: create a trigger so the second loop can be avoided. The DAQmx/Hardware does might not support the trigger on both edges on two channels, but additional hardware like LS7084 o. HCTL2022 can help you to create the trigger signal. These little bugs are designed for incremental encoders and create a pulse for every change in the A B lines
Greetings from Germany
Henrik
LV since v3.1
“ground” is a convenient fantasy
'˙˙˙˙uıɐƃɐ lɐıp puɐ °06 ǝuoɥd ɹnoʎ uɹnʇ ǝsɐǝld 'ʎɹɐuıƃɐɯı sı pǝlɐıp ǝʌɐɥ noʎ ɹǝqɯnu ǝɥʇ'

PCI-6602 Triggered event counting DAQmx

Hi
I'd like to use simple event counting using PCI-6602 (DAQmx) with an internally generated trigger pulse.
But I don't know how to figure out the error message when I use DAQmx Start Trigger.vi
Thanks
Kyu Young
Attachments:
EventCountingTrig.vi ‏21 KB

I'm sorry. I've solved it.

Getting 2nd TIO of the PCI6602 to perform buffered event counting via register-level programming

I got the first PCI6602 TIO to perform buffer event counting using interrupt. However, I could not get the second TIO working. I think I have initialized the proper registers in order to work with the second TIO, i.e.
1. Addressing all registers of the second TIO at 0x800 offset.
2. Binding the clock to counter 4-7 (set 0x00200000 to the Clock Configuration register). I am using the internal Timebase_3 clock which is 80MHz.
3. Tried setting 0x8000 to the Global Interrupt Control register at both its offset location (with 0 offset) and with 0x800 offset (2nd TIO offset location).
Am I missing something here? I got no interrupts from the PCI bus and I got 0xff
ff when I tried to read the Status register.

Al,
I have been experimenting with the 6602, but I have not been able to see any of the interrupts generated by the counters. I have tried both TC mode and an external signal on a single GATE (G0). The Gi_Status_Register indicates that the interrupts are occuring (appropriately for each mode), but I can't see them on the bus (my interrupt handler is never invoked; cat /proc/interrupts shows 0 interrupts).
Could you pass along any tips on how you did it?
Thanks!
-Rob

Why is buffered event counting cumulative

I'm trying to do buffered event counting using general purpose counters on an e-series board. It doesn't work quite as advertised. Each point in the buffer is supposed to contain the count of source events that occurred between successive pulses of the gate, according to the Nidaq function reference manual. I find, however, that every point contains the cumulative number of events, so the data are monotonically increasing. Is there a setting somewhere to change this behavior, or is there an error somewhere - either in the documentation, or in the code?
This was with NI boards 6711 and a 6035 in a G4 running OS 9.

Gus said:
"Where in the documentation does it suggest that buffered event counting is not cumulative?"
page 8-51, NI-DAQ software reference for Macintosh. The example shows the buffer containing values of 4, 2, and 5, corresponding to the number of events between consecutive transitions of the gate, not the cumulative total of events since counting started.
I have just checked to ensure that buffered period measurement is not cumulative, and it is not (which is good).
Thanks for the tip.
jamie

Want to trigger event count from both counters (E) to buffer using FOUT (100kHz/16 or slower) as a trigger

We are using a AT-MIO-16E-1 board. We would like to run an xy raster pattern from the buffer (AO) in order to reduce scan times (256 x 256 pt images). At each AO (voltage) point we would like to read from both onboard counters and store the number of events counted to memory, reading out the buffer say every 256 pts (1 scan line). In order to ensure accurate counting periods the counters need to be triggered to coincide with some "dwell time" at each AO voltage pt. We have thought of using FOUT for the trigger or perhaps out analog out scanning signal but are concerned that the FOUT freq is too high (6250 khz - we would like 100hz-10khz). Any suggestions or e
xamples would be appreciated.

Hello;
The main problem there is going to be the counter triggering. I'm saying that because, there isn't a way for the Analog Input operation to send pulses that will trigger of the timer operation at multiple voltage levels. The only solution for this I can think of is, instead of having an analog voltage level which would indicate the position of xy, if you could have a device which would give a TTL pulse instead when the desired position is reached, then you could use the 6601 to have a triggered operation at the counter. Another constraint for your application right now is the fact that the E-series boards' counters don't have triggering features, only gated features.
Anyway, you would need to have a TTL pulse either to trigger (in case of the 6601 count
ers) or to gate (in case of the E-series board), when the desired XY position is reached.
Meanwhile, you can refer to the Labview examples for Streaming to disk, Analog I/O and counter operations. You can go to Search Examples->I/O Interfaces->Data Acquisition->Data Logger ( for streaming to disk operations); Search Examples->I/O Interfaces->Data Acquisition->Analog Output ( for Analog Output Operations); and Search Examples->I/O Interfaces->Data Acquisition->Counters (for counter operations). Also; I'm including an Application Note which talks about synchronization of multiple DAQ tasks I think will be helpful for you also.
Regards.
Filipe
Attachments:
Advanced_Sync_Techniques_for_DAQ.pdf ‏189 KB

M-Series Buffered Event Counting with DMA -- gating problem

Hi --
I am implementing DMA-based buffered event counting on a PCIe-6259 board. I use G0_Out as the gate for G1, which counts events on a PFI pin. So by setting the speed of G0, I get an event count (either cumulative or non-cumulative) on a periodic basis, which is directly DMA'd to my buffer, and synchronized with other i/o operations.
This is working well right now, except for one problem, which is that the I only get data if there is at least one source edge between gates. i.e. if there are no edges, nothing gets pumped to the dma buffer.
I am guessing that a stale data error is somehow choking off the DMA transfer from the counter. Is that possible?
Is there some magic that I need to do to avoid this, because for this application, especially if I am counting cumulatively, I don't care about a missing edge, but I do care if the dma transfers get out of phase with the rest of my timing.
Thanks in advance for any help!
--spg
Here is a snippet of the code that sets up the event counting on G1, partly based on gpctex6.cpp:
const int sDMASelect[] = {1,2,4,8,3,5};
// source: pfi, or -1 for 20Khz clock
void eventTimerSetup(tMSeries *board, tTIO *tio, int dmaChannel, bool cumulative, int source)
   int sourceSelect = (source==-1) ? 0 : (source+1);
   //MSeries.CTR.Source
   tio->G1_Input_Select.setG1_Source_Select(sourceSelect); // (pfi+1) or 20Khz=0
   tio->G1_Input_Select.setG1_Source_Polarity(0); //rising=0
   tio->G1_Input_Select.setG1_OR_Gate(0);
   tio->G1_Input_Select.flush();
   //MSeries.CTR.Gate
   tio->G1_Input_Select.setG1_Gate_Select(20); //the G_OUT signal from other clock=20
   tio->G1_Input_Select.setG1_Output_Polarity(0); //active high=0
   tio->G1_Input_Select.flush();
   //MSeries.CTR.IncrementRegisters
   tio->G1_AutoIncrement.writeRegister(0);
   //MSeries.CTR.InitialCountRegisters
   tio->G1_Mode.writeG1_Load_Source_Select(tTIO::tG1_Mode::kG1_Load_Source_SelectLoad_A);
   tio->G1_Load_A.writeRegister(0);
   tio->G1_Command.writeG1_Load(1);
   tio->G1_Load_B.writeRegister(0);
   tio->G1_Load_A.writeRegister(0);
   tio->G1_Command.setG1_Bank_Switch_Enable(tTIO::tG1_Command::kG1_Bank_Switch_EnableBank_X);
   tio->G1_Command.setG1_Bank_Switch_Mode(tTIO::tG1_Command::kG1_Bank_Switch_ModeGate);
   tio->G1_Command.flush();
   //MSeries.CTR.ApplicationRegisters
   tio->G1_Input_Select.setG1_Gate_Select_Load_Source(0);
   tio->G1_Mode.setG1_Reload_Source_Switching(tTIO::tG1_Mode::kG1_Reload_Source_SwitchingAlternate);
   tio->G1_Mode.setG1_Loading_On_Gate(cumulative ? tTIO::tG1_Mode::kG1_Loading_On_GateNo_Reload : tTIO::tG1_Mode::kG1_Loading_On_GateReload_On_Stop_Gate);
   tio->G1_Mode.setG1_Loading_On_TC(tTIO::tG1_Mode::kG1_Loading_On_TCRollover_On_TC);
   tio->G1_Mode.setG1_Gating_Mode (tTIO::tG1_Mode::kG1_Gating_ModeEdge_Gating_Active_High);
   tio->G1_Mode.setG1_Gate_On_Both_Edges (tTIO::tG1_Mode::kG1_Gate_On_Both_EdgesBoth_Edges_Disabled);
   tio->G1_Mode.setG1_Trigger_Mode_For_Edge_Gate(tTIO::tG1_Mode::kG1_Trigger_Mode_For_Edge_GateGate_Does_Not_Stop);
   tio->G1_Mode.setG1_Stop_Mode(tTIO::tG1_Mode::kG1_Stop_ModeStop_On_Gate);
   tio->G1_Mode.setG1_Counting_Once(tTIO::tG1_Mode::kG1_Counting_OnceNo_HW_Disarm);
   tio->G1_Second_Gate.setG1_Second_Gate_Gating_Mode(0);
   tio->G1_Input_Select.flush();
   tio->G1_Mode.flush();
   tio->G1_Second_Gate.flush();
   //MSeries.CTR.UpDown.Registers
   tio->G1_Command.writeG1_Up_Down(tTIO::tG1_Command::kG1_Up_DownSoftware_Up); //kG1_Up_DownSoftware_Down
   //MSeries.CTR.OutputRegisters
   tio->G1_Mode.writeG1_Output_Mode(tTIO::tG1_Mode::kG1_Output_ModePulse);
   tio->G1_Input_Select.writeG1_Output_Polarity(0);
   //MSeries.CTR.BufferEnable
   board->G1_DMA_Config.writeG1_DMA_Reset(1);
   board->G1_DMA_Config.setG1_DMA_Write(0);
   board->G1_DMA_Config.setG1_DMA_Int_Enable(0);
   board->G1_DMA_Config.setG1_DMA_Enable(1);
   board->G1_DMA_Config.flush();
   tio->G1_Counting_Mode.setG1_Encoder_Counting_Mode(0);
   tio->G1_Counting_Mode.setG1_Alternate_Synchronization(0);
   tio->G1_Counting_Mode.flush();
   //MSeries.CTR.EnableOutput
   //board->Analog_Trigger_Etc.setGPFO_1_Output_Enable(tMSeries::tAnalog_Trigger_Etc::kGPFO_1_Output_EnableOutput);
   //board->Analog_Trigger_Etc.setGPFO_1_Output_Select(tMSeries::tAnalog_Trigger_Etc::kGPFO_1_Output_SelectG_OUT);
   //board->Analog_Trigger_Etc.flush();
   //MSeries.CTR.StartTriggerRegisters
   tio->G1_MSeries_Counting_Mode.writeG1_MSeries_HW_Arm_Enable(0);
   board->G0_G1_Select.writeG1_DMA_Select(sDMASelect[dmaChannel]);
   tio->G1_Command.writeG1_Arm(1); // arm it
Scott Gillespie
http://www.appliedbrain.com
scott gillespie
applied brain, inc.
Solved!
Go to Solution.

Okay, I have it working now. In addition to your suggested changes, I had to remove the following line:
tio->G1_MSeries_Counting_Mode.writeG1_MSeries_HW_Arm_Enable(0);
It appears that writing something to MSeries_Counting_Mode causes that register to supersede the Counting_Mode register. Is that right?
So code that now works for me is listed below.
thanks Tom!
-spg
void eventCounterSetup(tMSeries *board, tTIO *tio, int dmaChannel, bool cumulative, int source) // pfi, or -1 for 20Khz clock
int sourceSelect = (source==-1) ? 0 : (source+1);
//MSeries.CTR.Source
tio->G1_Input_Select.setG1_Source_Select(sourceSelect); // (pfi+1) or 20Khz=0
tio->G1_Input_Select.setG1_Source_Polarity(0); //rising=0
tio->G1_Input_Select.setG1_OR_Gate(0);
tio->G1_Input_Select.flush();
//MSeries.CTR.Gate
tio->G1_Input_Select.setG1_Gate_Select(20); //the G_OUT signal from other clock=20
tio->G1_Input_Select.setG1_Output_Polarity(0); //active high=0
tio->G1_Input_Select.flush();
//MSeries.CTR.IncrementRegisters
tio->G1_AutoIncrement.writeRegister(0);
//MSeries.CTR.InitialCountRegisters
tio->G1_Mode.writeG1_Load_Source_Select(tTIO::tG1_Mode::kG1_Load_Source_SelectLoad_A);
tio->G1_Load_A.writeRegister(0);
tio->G1_Command.writeG1_Load(1);
tio->G1_Load_B.writeRegister(0);
tio->G1_Load_A.writeRegister(0);
tio->G1_Command.setG1_Bank_Switch_Enable(tTIO::tG1_Command::kG1_Bank_Switch_EnableBank_X);
tio->G1_Command.setG1_Bank_Switch_Mode(tTIO::tG1_Command::kG1_Bank_Switch_ModeGate);
tio->G1_Command.flush();
//MSeries.CTR.ApplicationRegisters
tio->G1_Input_Select.setG1_Gate_Select_Load_Source(0);
tio->G1_Mode.setG1_Reload_Source_Switching(tTIO::tG1_Mode::kG1_Reload_Source_SwitchingAlternate);
tio->G1_Mode.setG1_Loading_On_Gate(cumulative ? tTIO::tG1_Mode::kG1_Loading_On_GateNo_Reload : tTIO::tG1_Mode::kG1_Loading_On_GateReload_On_Stop_Gate);
tio->G1_Mode.setG1_Loading_On_TC(tTIO::tG1_Mode::kG1_Loading_On_TCRollover_On_TC);
tio->G1_Mode.setG1_Gating_Mode (tTIO::tG1_Mode::kG1_Gating_ModeEdge_Gating_Active_High);
tio->G1_Mode.setG1_Gate_On_Both_Edges (tTIO::tG1_Mode::kG1_Gate_On_Both_EdgesBoth_Edges_Disabled);
tio->G1_Mode.setG1_Trigger_Mode_For_Edge_Gate(tTIO::tG1_Mode::kG1_Trigger_Mode_For_Edge_GateGate_Does_Not_Stop);
tio->G1_Mode.setG1_Stop_Mode(tTIO::tG1_Mode::kG1_Stop_ModeStop_On_Gate);
tio->G1_Mode.setG1_Counting_Once(tTIO::tG1_Mode::kG1_Counting_OnceNo_HW_Disarm);
tio->G1_Second_Gate.setG1_Second_Gate_Gating_Mode(0);
tio->G1_Input_Select.flush();
tio->G1_Mode.flush();
tio->G1_Second_Gate.flush();
//MSeries.CTR.UpDown.Registers
tio->G1_Command.writeG1_Up_Down(tTIO::tG1_Command::kG1_Up_DownSoftware_Up); //kG1_Up_DownSoftware_Down
//MSeries.CTR.OutputRegisters
tio->G1_Mode.writeG1_Output_Mode(tTIO::tG1_Mode::kG1_Output_ModePulse);
tio->G1_Input_Select.writeG1_Output_Polarity(0);
//MSeries.CTR.BufferEnable
board->G1_DMA_Config.writeG1_DMA_Reset(1);
board->G1_DMA_Config.setG1_DMA_Write(0);
board->G1_DMA_Config.setG1_DMA_Int_Enable(0);
board->G1_DMA_Config.setG1_DMA_Enable(1);
board->G1_DMA_Config.flush();
// from Tom:
// The "magic" you need is referred to as synchronous counting mode (or Duplicate Count Prevention in NI-DAQmx).
// Try setting G1_Encoder_Counting_Mode to 6 (synchronous source mode) and G1_Alternate_Synchronization to 1 (enabled).
tio->G1_Counting_Mode.setG1_Encoder_Counting_Mode(6); // 0
tio->G1_Counting_Mode.setG1_Alternate_Synchronization(1); // 0
tio->G1_Counting_Mode.flush();
board->G0_G1_Select.writeG1_DMA_Select(sDMASelect[dmaChannel]);
tio->G1_Command.writeG1_Arm(1); // arm it
scott gillespie
applied brain, inc.

Doing Buffered Event count by using Count Buffered Edges.vi, what is the max buffer size allowed?

I'm currently using Count Buffered Edges.vi to do Buffered Event count with the following settings,
Source : Internal timebase, 100Khz, 10usec for each count
gate : use the function generator to send in a 50Hz signal(for testing purpose only). Period of 0.02sec
the max internal buffer size that i can allocate is only about 100~300. Whenever i change both the internal buffer size and counts to read to a higher value, this vi don't seem to function well. I need to have a buffer size of at least 2000.
1. is it possible to have a buffer size of 2000? what is the problem causing the wrong counter value?
2. also note that the size of max internal buffer varies w
ith the frequency of signal sent to the gate, why is this so? eg: buffer size get smaller as frequency decrease.
3. i'll get funny response and counter value when both the internal buffer size and counts to read are not set to the same. Why is this so? is it a must to set both value the same?
thks and best regards
lyn

Hi,
I have tried the same example, and used a 100Hz signal on the gate. I increased the buffer size to 2000 and I did not get any errors. The buffer size does not get smaller when increasing the frequency of the gate signal; simply, the number of counts gets smaller when the gate frequency becomes larger. The buffer size must be able to contain the number of counts you want to read, otherwise, the VI might not function correctly.
Regards,
RamziH.

Gated-event counting using analog triggers?

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