03-07-2021 03:47 PM
Hi,
does the PCI 6602 support hardware-timed DIO?
thanks!
03-07-2021 10:00 PM
No it does not. It's replacement, the PCIe-6612, does.
What are your DAQ requirements, what DAQ hardware do you already have, and can you purchase anything new if you need it to meet your requirements?
-Kevin P
03-08-2021 02:17 AM
Hi Kevin,
thanks for the help, I'd like to synchronise three digital output channels (one to external trigger a camera, two for laser control). Do you know if this is still possible?
thanks,
anna
03-08-2021 07:42 AM
It will depend on how regular the timing relationships are among all the signals. If entirely regular, there's a good chance it's possible.
You'd end up using counter tasks to deliver hardware-timed digital pulses. They'll still be TTL-logic compatible digital signals, but they'll come from the counter subsystem of the board instead of the "regular" DIO subsystem.
Some keywords that can help you
- "Arm Start Trigger"
- "initial delay"
- "retriggerable single pulse"
I might be able to help more if you can describe the needed timing relationships in detail, including both any input signals to react to and output signals to generate.
-Kevin P
03-08-2021 08:20 AM
Thanks! The timing is entirely regular.
I have two lasers and a camera (andor ixon 897) connected to the PCI 6602. I'd like to have it so that the lasers alternate (e.g. every 10ms) and each time they alternate, the camera starts a new frame (so exposure 10ms). i.e. the start of the frame is synchronised with the laser alternation. I originally thought this could be done by using the camera internal triggering to trigger the lasers but since PCI 6602 does not accept hardware time DIO, I guess I have to go the other way round and use the camera on external triggering?
In this case, the lasers would require digital ouputs that are triggered by the rising/falling edge of a counter? and the camera would need some sort of waveform?
03-08-2021 07:42 PM
If I understand your system correctly, I see it like this:
You'd have 3 pulse train tasks with their timing sync'ed by a combo of an "Arm Start Trigger" and careful coordination of their timing parameters (high time, low time, initial delay). Each would drive one of your 3 devices.
If you want to configure them as *finite* pulse trains, be aware that each task will consume 2 of your board's 8 total counters - both the one you configure explicitly and the one it's "paired" with. Pairs are { (0,1), (2,3), (4,5), (6,7) }. So this takes 6 counters total.
Or you can configure as continuous and decide in software when to stop them. This takes 3 counters total.
-Kevin P