Hi all,
System - Windows NT4.0, LabView 7.0, PCI-DIO-96 card.
Info -
I am using the "DIO single read/write.vi" to update ports on a custom
board. The Labview code has an outer For Loop that executes 64 times
(to update the ports 64 times). Inside the loop is a sequence
structure. The first sequence frame uses PPI B Port A of the DIO-96
in output Mode 0 (no handshake) to update one target port. The next
frame uses PPI A Port A in output Mode 1 (handshake) to update a
different target port. The DIO PPIs are always used in the same Mode
and the same data direction.
Question 1 -
When the vi executes, does it look at the iteration input and leave
the PPI config register alone if the iteration input is nonzero?
Specifically, during my system init routine, the input is wired to the
iteration terminal of the For Loop. Later in the code (after exiting
init) the vi is used to do updates in other structures. I want all
subsequent executions of the vi to be the same configuration as
initialized. If I tie a nonzero numeric constant to the iteration
input of the vi during subsequent executions, will the vi leave the
8255 in the same configuration as when the init routine was exited?
Question 2 -
I need to wait for the handshake in the second sequence frame to
complete before the sequence is exited. I assume that when the vi is
used inside of a sequence, it is analagous to a subroutine call. Does
the vi wait for the handshake to complete before returning? In other
words, will the vi complete the handshake with my target port before
the sequence frame is exited? If not, any suggestions on how to wait
for the completion?
TIA - Charlie
