Gated semiperiod counting DaqMY LV7.0 + NI6602

I am converting an application form traditional DAQ to DaqMX and am having trouble with the new conventions.
The application uses a common gate to count gated events on multiple counters (5 total counters employed). An event causes 5 pulses of 500us 0.5 duty cycle and the counters must share this gate source and count TTL pulses coming from 4 different photon counting PMT. Essentially I am measuring a optical decay curve (10 points of each 500 microseconds)when each event occurs. This was easily accomplished using traditional DAQ but I cant get it to work under DaqMX (version 7.2). My solution for this scheme under traditional DAQ was to set up 5 tasks, Task 1-4 used counters 0-3 on the 6602 set for semiperiod buffered counting from the source terminal of each counter and the gate was configured to share a common PFI line counter 5 also shared the common gate but used the internal 80MHz clock as a source (This was so I could have a time stamp of each event since the freqency of everns is not a constant. When setting up a semiperiod under DaqMX I can not get the source to change from the internal clock to the PFI corresponding to a counters "source" pin. Any help would be greatly appreciated.
-Paul
Paul Falkenstein
Coleman Technologies Inc.
CLA, CPI, AIA-Vision
Labview 4.0- 2013, RT, Vision, FPGA

Thanks for the help, I was able to get my application to work perfectly, I created a semi-period counting channel then set the timing to implicit continious timing and modified the following channel properities:
1. CI.Dup.CountPrevention = True (I need to allow for zero counts to be valid)
2. CI.SemiPeriod.Term = gate pfi (this allows me to gate multiple channels on a single pfi line)
3. CI.CtrTimeBaseSrc = Source (Pfi line wiered to my PMT ttl line, this is what I need to count)
4. CI.CtrTimebaseRate = 200000 (Maximum expected rate of TTL source pulses, is actually usually much slower ~1-1000kHz)
5. CI.CtrTimeBaseActiveEdge = rising (probably not needed)
6. CI.DataXferMech to DMA (since the 6602only has 3 DMA channels and I configured 4 channels in this mannor, I had to set the last channel to Interrupt, but the application has no trouble keeping pace with the data.
After configuring the channel I start each channel then read them in a loop, now everything is working great, thanks for pointing me in the reight dirrection
-Paul
Paul Falkenstein
Coleman Technologies Inc.
CLA, CPI, AIA-Vision
Labview 4.0- 2013, RT, Vision, FPGA

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