VXI VT1422A - Manual (Page 201)

Creating and Running Algorithms 199 Chapter 6
NOTES
1. Channels referenced by algorithms when they are defined are only
placed in the channel list before INIT. The channel list cannot be
changed after INIT. If an algorithm is re-defined (by swapping) after
INIT and it references channels not already in the channel list, it will
not be able to access the newly referenced channels. No error
message will be generated. To make sure all required channels will be
included in the channel list, define <alg_name> and re-define all
algorithms that will replace <alg_name> by swapping them before
INIT is sent. This insures that all channels referenced in these
algorithms will be available after INIT.
2. The driver only calculates overall execution time for algorithms
defined before INIT. This calculation is used to set the default output
delay (same as executing ALG:OUTP:DELAY AUTO). If an
algorithm is swapped after INIT that take longer to execute than the
original, the output delay will behave as if set by ALG:OUTP:DEL 0,
rather than AUTO (see ALG:OUTP:DEL command). Use the same
procedure from note 1 to make sure the longest algorithm execution
time is used to set ALG:OUTP:DEL AUTO before INIT.
An example program file named "swap.cpp" on the drivers CD shows how
to swap algorithms while the module is running. See Appendix G page 491
for program listings. View the readme.txt file provided with the
VXIplug&play driver for example program file location.