There's a reasonable description with FSM diagrams in C++
Communiccations Utilities, Holmes & Flanders, Ziff Davis Press, ISBN
1-56276-110-2. Also has a disc with C++ and 8086 asm.

If you can't find a copy I could scan the relevant pages but don't tell
Ziff I said that.

Matt Bonner wrote:
>
> I've been searching, but can't find much on this.
>
> Does anyone have a description (flow-chart, algorithm, etc) of the
> Xmodem protocol?  I prefer the Xmodem-1K version (sometimes called
> Ymodem) since it supports CRC instead of checksum error detection.
>
> --Matt

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Chris Savage, CTIV Ltd, Egham UK
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