Hi Ralph,
NI Compact DAQ uses the STC2 chip to provide timing signals to all the
modules over the back plane. Because of this every module will use the
same sample clock, so if you have simultaneously sampling modules then
these will all be syncronised. Correspondingly you can use the same
sample clock to driver the analog output. How ever your scan rate will
be determined by the slowest modules in you scan list.
Regards
Jon Bowers
Applications Engineer
NIUK