[Coco] Socat drivewire relay to CoCo1

[Tormod Volden]

On Mon, Mar 2, 2015 at 8:26 PM, jon bird wrote:
> That checksum of $f9f7 is fairly consistent (although I have seen a few
> instances where it comes back with something completely different). The
> "good" trace I posted yesterday shows the server accepting a checksum of
> $ff00.
>
> Possibly a bit of a random angle but I attempted to compute the checksum
> myself given the algorithm at the back of the Drivewire 3 spec. For a buffer
> set entirely to $ff I get a result of $FE01 which doesn't tally up with any
> of this.
>
> I'm at a bit of a loss now to explain what exactly is causing this.

To investigate further, I would have made a little DriveWire client
that prints out all received bytes on the CoCo, so that you would see
if it is the incoming data that gets corrupted or the outgoing
checksum. See for instance the DWDOS code in toolshed, or my DWLOAD
code at the Dragon forum.

Of course, you may also be able to PEEK the incoming data if you know
where the DIR command buffers it - if it is not in the command line
buffer :) Although it may use the same buffer to send the checksum and
receive the status byte so it might be partly overwritten.

Tormod