Ian,
I am assuming that you have the "DDC Clock Out" signal physically
connected to the "STROBE" input. In this fashion, you can use
STROBE as your acquisition clock source. However, this requires
that the generation sample clock be explicitly exported to the DDC
connector. To do this, you can call the niHSDIO Export Signal
vi. Select sample clock for export and make sure you pick the
correct output terminal ("ClkOut on Digital Data & Control Connector"). When the session is commited, this clock
will be driven to the DDC CLK OUT signal on your cable and looped back
to STROBE through your system. You have to make sure this clock
is completely routed before you try to start your acquisition. If
the clock is not yet being exported and you try to initiate the
acquisition, the task will timeout with a clocking error such as the
one you've seen.
For a good example on simultaneous generation and acquisition, I
might recommend referring to the example shipped with NI HSDIO called
"Dynamic Generation and Acquisition-Source Synchronous". This
example has a generation task export a sample clock and an acquisition
task that uses that clock. If you correctly have the two signal
connected at the end of the cable then you should be golden.
-Ryan
Message Edited by Ryan M on 03-14-2006 09:00 AM
