07-09-2013 09:41 AM
You are using the wrong baud rate for the Uno. The Uno uses 115200 for a baud rate. However, you can also simply delete the inputs for the baud rate and board type and they will default to Uno settings.
07-09-2013 10:15 AM
Many thanks! Works smoothly both on Uno and Mega.
07-10-2013 01:04 PM
I have realized that this VI works only with bank-A in "write" and bank-B in "read" mode. No other arrangement is currenly working.
10-11-2013 06:51 AM
After working with it for a while more, I ended up making sub-vi which can be used to put the MCP23017 in read or write mode (bank A and B in same mode). Now, I can atleast use the IC as a 16 bit input or output from labview thru arduino. I am working on a demo program. I'll upload everything later.