Variable fixed length digital reads

[bmewolf]

I am performing high speed burst mode digital input using a 6533. I need to perform fixed length transfers with programmable length from the port.  I am reading from different devices on the same bus so I must have the transfers start and stop (can't use continuous mode). It seems to not matter how many bytes I ask for in the read call, the device always performs the number of transfers specified in the Burst
Mode configuration call.  If I try to reprogram the burst mode length using a configuration call, I get an error  telling me I can't do this unless I
shutdown and restart the task.
Is there anyway around this? I tried using readRaw, the  description sounds like it might work, but it also gets the number of bytes for each burst mode read from the configuration call. help.

Pat

[Allen H]

Hi Pat,

The 6533 will attempt to acquire data in burst mode as long as there is space in its buffer and if the pause trigger is not asserted.  Have you tried using the pause trigger to control when the 6533 acquires its data?  By default, PFI 2 is the pause trigger if you are using ports 0, 0-1, or 0-3, and PFI 3 if using ports 2 or 2-3.

How many channels are you using?

Allen