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VB6, MSComm, and working in BINARY mode.

CVSmarc asked
Medium Priority
Last Modified: 2013-12-26
I am using VB6 and the MSComm control.
I have written several programs using the above and they are working OK. So I'm not a beginner to the concepts :>

I am working with a device that I can communicate to using  RS232.  The way it works is this

Send a REQ
Get and ACK
Send a Get Data request
Data is recieved in 8 blocks of 128 characters. I send an REQ after each 128 block.

The difficulty I am having is that sometime I get only hald of the data. I suspect that because I am using  the TEXT mode I am getting a character that is blocking transmission (Likie and EOF, Cntrl Z, or something like that)

I would like to try working in BINARY mode however I can find little information about that. Does anyone have some example on this which shows  how I processes that data coming in in the MSComm event routine. After recieving I will still need to deal with the data as strings for comparisons.

Many thanks
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