Hi densmore,
Mike is correct about using the analog input and analog
output tasks in separate programs. One example of this would be to use a
LabVIEW program to control the analog output channels while using the test
panel in Measurement and Automation Explorer (MAX) to acquire data on the
analog input channels. Because each runs in a separate task, they can be used
in separate programs.
To clarify your first question, for the M Series boards, there
is an independent DAC for each analog output channel, though they do share the
same FIFO and sample clock. Because each channel shares the same FIFO, the data
must be read from the FIFO to each DAC in the proper order between sample
clocks. The channels will then all update at the same time, based on when the
sample clock arrives, but the time it takes to transfer each value from the
FIFO to the DAC will increase as you add more channels. As the DACs are loaded with new values, the channels will retain their previous value until the next
update from the sample clock. Please refer to the discussion, "Update rates on analog outs M-series", for more information on how the FIFO and DACs update. Hope this helps,
Daniel S.
National Instruments
