CFA-635 communication


New member

I just bought a CFA-635 with the intent of designing my own control application. However, I can't make a shred of sense from the C source for Wintest, all I really need is the communication protocol + command codes. Is this documented anywhere? Here is my following understanding of the communication I have managed to figure out on my own:

module transmits a byte roughly 2 times per second, which only has about 3 possible values...purpose of this unknown.

every keypress/release also generates 1 byte of tx. Specific codes unknown.

sending data to module must be:
1 byte command code + 1 byte datalength + datalength bytes data + 2? byte crc.

command codes, parameters, or pretty much anything else is unknown to me...but wouldn't this all be clearly documented somewhere?

I've looked around at the other discussions, but none seem to be concerned with the 635, and most of it is code/language specific, which leads me down endless rabbit holes. Any help would be appreciated.
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New member
One more thing...

I do, at least, know the character codes, since wintest lets me get a readout of them. However, I'd LOVE to be able to overwrite some of them/design custom characters. Is this possible? (most notably, I'd like to make the 81 charactes necessary to make a 2-band/character wave analyzer)

also, I assume that there is a way to "discover" the panel by scanning available com ports...
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