This article is from the Apple II GNO FAQ, by Devin Reade with numerous contributions by others.
A#8.9: This answer describes hooking up a terminal to the printer port.
Hooking one up to the modem port will be similar except that
.ttya should be used instead of .ttyb.
On the hardware side, you will need a mini DIN 8 to DB25 printer
cable. This should be connected from the IIgs' printer port
to the port on the terminal that would normally be hooked to
a modem.
Next, you have to run a getty(8) over the printer port. Add
this line to your /etc/inittab file:
pp:23478:rest::/usr/sbin/getty 8bit.xxxx .ttyb
where xxxx is the speed. Remove '78' from '23478' if you want
to run it only in multiuser mode. See also Q#8.8 regarding
initialization of the serial port.
In order for the change to take effect, you either have to quit
and restart GNO, or type '/bin/init q' (without the quotes).
 
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