[NTLK] eMate hinge repaired, but struggling to get PT100 terminal working under OpenBSD

[Morgan Aldridge]

Hey all,

First, my apologies for cross-posting this here, but I know we've got quite
a few hardware and serial pros who might be able to help.

I had put my eMate away in 2014 to not use until I had performed
preventative maintenance on the hinges, which I finally started in March
and -- after getting a new soldering iron -- completed last week in advance
of GNUM #12. I still need to re-cell the battery and upgrade the memory,
but I'm primarily planning to use this as a serial terminal on my primary
OpenBSD workstation.

In 2014 I had it running as a serial terminal using getty under Mac OS X on
a (probably 2012) Intel MacBook Pro, my Keyspan/Tripp-Lite USA-19HS USB
serial adapter, the original Apple Newton PC serial cable (DB-9 to mini
DIN-8), and PT100 running on the eMate. I now have the eMate connecting to
my OpenBSD amd64/7.4-stable workstation (a 2015 13in i7 MacBook Air) via
the same USA-19HS, serial cable, and PT100 at 9600 baud 8N1 and no flow
control and it gets a login prompt, but regardless of what character I
enter on the eMate (keyboard or written into the input line), it just
resends the login prompt.

It's been so long since I used serial regularly (even my MessagePad 2100
was almost always connected via ethernet, WiFi, or occasionally Bluetooth)
that I've had to re-research the details and try nearly every possible
configuration permutation on the OpenBSD & PT100 sides of things. Lots of
technical details here in my post to the OpenBSD misc@ mailing list:

<https://marc.info/?l=openbsd-misc&m=169811875524832&w=2>

So, if my description of this issue sparks any ideas, please share them and
I'll gladly give them a try. In the aforemented post to misc@, I did list
some of my next steps to try to narrow this down to software configuration,
drivers (OpenBSD has a driver specifically for the Keyspan USA-19HS), or
hardware (esp. eMate -- having just been repaired and not having seen
leaking caps -- or USA-19HSS).

Thanks for all the inspiration, folks!

-- 
Morgan
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