Date   : Wed, 06 May 1987 15:33:08 GMT
From   : beta!dzzr@hc.dspo.gov (Douglas J Roberts)
Subject: A problem with my parallel output port (HELP, please)

I recently stuck an external modem on my old Northstar, using the
second of its two serial ports. I then constructed a parallel cable,
removed the serial interface card from the Epson MX-80, and modified
my LifeBoat Associates CP/M 2.21 using MOVCPM and SYSGEN to tell
the system that the printer was now on the parallel output port.

What reached the printer was (seemingly) bit-shifted garbage. The
handshaking worked fine, but I suspect that the printer driver in my
CPM is fouled.

I then wrote a little 8080 test code to send characters to the
parallel output port, and it worked fine. I would like to modify
my USER.ASM file to include a parallel port driver that I know
works, but I don't know how to patch the user stuff into CPM after 
I'm done.

Can anyone out there in NETLAND help? (Keith, are you listening?)

Thanks in advance for all the good help....

--Doug Roberts