What?

That's completely self defeating. The A/D converter already put's out 0-1023.

1023/1023*256 *10=2560
With the */ operator, all your formula does is multiply it times 2560 and divide by 256, which is the same as just saying ADval * 10.

So you would actually be sending 10230.
I don't think that's what you wanted.

If you want to send 0-1023 to the PC, just send the ADval.
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