I am about to buy a NI9401 which will be connected to a NIcDAQ-9171. But I am now testing the NI9401 with a NicDAQ-9172.
My objective is to record simultaneous the position of 2 encoders (using 2 counters input of the DAQ). With the NIcDAQ9172 I have, there is only 2 counters; but there are 4 in the NIcDAQ 9171.
My problem is that, will it be possible to record both counters simultaneous with the NI9401, using the session based interface in Matlab. This is important to me because some NI engineer told me so, but testing with the NIcDAQ9172, i have problems to record only one encoder in the same time as a clock input (that seems to be necessary in order to measure counter position) : I obtain a message saying "the hardware associated with the session is reserved..." . I don't know how to proceed to solve this problem and I am afraid
that this could be the same with the NIcDAQ-9171.
Thanks for your help, because that will really be helpfull to be chure of my material choice.