PE> I made the rash assumption that putting a delay before the ATA
PE> command could not possibly have an undesirable side-effects.

BL> It looks like the timing of the negotiation stage is critical.

You dont even know that. The AT commands that dont take immediate
effect can always be aborted with a single char. You can see that
with a dial command. Its quite possible it just aborts the ATA
command too if you send it a byte before its completed the answer.
@EOT:

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