On Wed, 28 Jul 2010 13:48:14 -0700, "Drew Maurer" said:

>=20
> Thanks.  Actually I've already 'scoped the levels in all directions, they
> look fine.  In fact that MAX233 is new but the problem is not - I added
> the
> 233 because I thought the problem might be related to the crude level
> shifter made out of discretes (which borrowed -12V from the PC itself)
> that
> I was using, but the problem persists unchanged.

On the PC is it a real serial port or a USB adapter under Windows? I had
problems once where a byte here and there was being munged, and a
different driver fixed it. Prolific PL-2303 based USB-Serial adapter.

Cheers,

Bob

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