Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/18/84; site brl-tgr.ARPA
Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxb!mhuxn!mhuxm!mhuxj!houxm!whuxlm!harpo!decvax!genrad!panda!talcott!harvard!seismo!brl-tgr!tgr!rmeier@Su-Star.ARPA
From: R. MEIER <rmeier@Su-Star.ARPA>
Newsgroups: net.micro.cpm
Subject: re:apple-cpm serial interface problems
Message-ID: <7783@brl-tgr.ARPA>
Date: Mon, 28-Jan-85 14:57:56 EST
Article-I.D.: brl-tgr.7783
Posted: Mon Jan 28 14:57:56 1985
Date-Received: Wed, 30-Jan-85 19:20:25 EST
Sender: news@brl-tgr.ARPA
Organization: Ballistic Research Lab
Lines: 25

Jim,
	I have the following arrangement of cards and have not had a problem.
		Slot 0:128K ram
		Slot 1:Super-Serial Card (modem)
		Slot 2:Apple Serial Card (printer)
		Slot 3:80-col card
		Slot 4:Z80 card
		Slot 5:vacant
		Slot 6:disk
		Slot 7:vacant
	Within the configuration block of CP/M, I have routines to make the
128K ram look like a disk, the Slot 2 Apple Serial Card look like a printer
with DTR flow control, and the Super-Serial Card look like another console.
The Apple Serial Card has no flow control on board, but since the printer
doesn't transmit, I switched the DTR and REC lines on the RS-232 connector.
The Apple Serial Card is nothing but a ROM, line driver, and line sensor
that I can read/write directly.  The ROM contains software for RS-232 timing,
so I use it to output a byte at a time, but I only send it a byte after
reading that the DTR line is high.  The Super-Serial Card has flow control
on board and so is called in the normal fashion of a port/status register
pair.
	If the above superficial view is helpful, then fine, otherwise,
write me at rmeier@star.arpa.
					Bob (rmeier@star.arpa)
------