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From: mort@apollo.HP.COM (Stephen Moriarty)
Newsgroups: comp.sys.apple2
Subject: Quadram APIC-A //e compatibility & code debugging
Message-ID: <50a3ec40.20b6d@apollo.HP.COM>
Date: 28 Mar 91 20:39 GMT
Sender: root@apollo.HP.COM
Organization: Hewlett-Packard Apollo Division - Chelmsford, MA
Lines: 32

I have an APIC-A parallel interface card. I'm attempting to hook
it up to a Qume Sprint-5 printer. The first incompatibility I
know of is that the APIC-A wants an ACK* (active low) signal, but
the printer doesn't have it. I've attempted to recreate it from
the signals the printer does have, with limited success. If I do
]pr #1, I get what I type on the printer, but I get a dump of
some memory address, as though I was in the monitor, following
the first character I type at the ] prompt, and following a
RETURN. Is the APIC-A compatible with the enhanced //e? The EPROM
has a label marked, "APIC-A c.1983".

Failing that, I'd like to debug the firmware. I've listed it out
from the Apple monitor. If I had a printer interface, I could get
a hardcopy ;(. I'm reading the chapter on the monitor in the //e
Technical Reference Manual, but don't see anything about single
stepping, or setting breakpoints. There must be an indirect way
to do this, perhaps using the BRK instruction. I thought of
copying the card's firmware to RAM and putting the RAM copy
starting address in CSW, you know, the COUT vector. I could then
use BRK instructions (can I?) to figure out what's going on.
That's so much easier than reading the instructions and
predicting the code execution.

Also, is there a way to redirect output to disk? I would like to
list the code to disk and be able to examine it with an editor.

Thanks for any and all help.


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