H89 as serial terminal

From: Patrick Rigney <patrick_at_evocative.com>
Date: Thu Mar 27 18:19:00 2003

> The hardware solution is to disconnect the internal serial cable from the
> termianl logic PCB (the rearmost vertical PCB in the machine) and replace
> it with one of the cables that goes to a DB25 connector on the back
> (these cables are normally connected to the serial port PCB plugged into
> the computer mainboard, just in front of the terminal logic PCB). The
> cables have a Molex 0.1" pitch SIL connector on the end, and fortunately,
> the pinout of all the internal serial connectors (terminal logic PCB,
> computer 'console port', serial port PCB) is the same.

Ouch...

> The software solution is to write a little program that transfers
> characters between the computer's console port and one of the other
> serial ports. This will then make the computer section appear as a
> transparent link between the terminal and the outside world.

much easier than any of the above... get a copy of MDM712 or similar
terminal emulation program. MDM712 comes with a serial port driver for
H8/89. Plug your device into the spare serial port on the back of the
(unopened) machine, and that should do it. Some '89's have three-port
serial cards... I don't know which ends up being which or whether MDM712
lets you choose, all of my '89's are down right now. :-/

Patrick
Received on Thu Mar 27 2003 - 18:19:00 GMT