I think you might just need to write a 1D array of booleans (1 channel N samples) instead of a 1D array of U32 integers. You might possibly also need to change the config setting to "one channel for EACH line".
When you write U32 data to the task, it gets mapped in a bitwise fashion to all the lines in the port. Bit 0 corresponds to line 0, bit 1 to line 1, etc. This will be true even if Bits 0, 1, 2, etc. aren't in the task. If you want to write to line 2, you'll need your U32 array to toggle between values of 0 and 4 because the value 4 corresponds to bit 2 and line 2. I'll bet your array toggles between values of 0 and 1, meaning it only toggles bit 0, and *that's* why it only works on line 0.
All this stuff is easier to deal with if you write a 1D array of booleans with only 1 channel in the task. Then the values are mapped to whatever channel was assigned to the task. I tend to avoid the U32 port writes for this reason. With Booleans, you send the same 1D array of values no matter what line you configure for the task. With U32's, the array of values needs to change when you configure a different line for the task.
(Note that when writing the U32 array, internal masking will prevent the task from actually changing DO signals on lines that aren't part of the task.)
-Kevin P
ALERT! LabVIEW's subscription-only policy came to an end (finally!). Unfortunately, pricing favors the captured and committed over new adopters -- so tread carefully.
