[comp.sys.atari.8bit] question on 800 and 850

G.ABRAMS@Score.Stanford.EDU.UUCP (01/25/87)

Return-Path: <guglielmo@nwc-143b.ARPA>
Received: from nwc-143b.ARPA by SU-SCORE.ARPA with TCP; Fri 23 Jan 87 08:05:12-PST
Date: 23 Jan 87 08:03:00 PST
From: <guglielmo@nwc-143b.ARPA>
Subject: question on 800 and 850
To: "info-atari-request" <info-atari-request@score.stanford.edu>
Reply-To: <guglielmo@nwc-143b.ARPA>

	I am using an Atari 800 and 850 Interface Module for a class
project and have run into a snag. I am attempting to connect the 800
with the control unit of the new Radio Shack Armatron robot through the
parallel port on the 850 and have the 800 drive the robot. The question
is does anyone know what the address of the parallel port is so that
I can do a "poke" to that address and have the levels set until I
change them?
	Could you please respond to me directly since I am not on
the INFO-ATARI8 mailing list. Thanks in advance.

					Gene Guglielmo
					guglielmo@nwc-143b
					work: 619-939-3661
					home: 619-446-5691
------
-------

cabbie@chinet.UUCP (01/25/87)

In article <12273590292.14.G.ABRAMS@Score.Stanford.EDU> G.ABRAMS@Score.Stanford.EDU (Info-Atari Moderator) writes:
>Return-Path: <guglielmo@nwc-143b.ARPA>
/
/	I am using an Atari 800 and 850 Interface Module for a class
/project and have run into a snag. I am attempting to connect the 800
/with the control unit of the new Radio Shack Armatron robot through the
/parallel port on the 850 and have the 800 drive the robot. The question
/is does anyone know what the address of the parallel port is so that
/I can do a "poke" to that address and have the levels set until I
/change them?
/	Could you please respond to me directly since I am not on
/the INFO-ATARI8 mailing list. Thanks in advance.
/
/					Gene Guglielmo
/					guglielmo@nwc-143b
/					work: 619-939-3661
/					home: 619-446-5691
/------

You cannot use the parallel printer port on the 850 for use like that.
The only way to present data in that fashion is to use the joystick ports
for that.  I have built an eprom programmer using that method, and found
that I could transmit and receive data about twice as fast as the 
SIO bus.  If you need additional info let me know.  It isn't as hard as 
it sounds.  It could be done with basic.  BTW I was sending serial data at
a undetermined baud rate.  

	Don't forget that you may have to buffer the output lines.


-- 
*******************************************************************************
Any opinions expressed above are my own.        Rich Andrews
 They can be yours too.  Please send $19.95 to.....ihnp4!chinet!cabbie
*******************************************************************************

ekijak@ARDEC.ARPA.UUCP (01/30/87)

I don't know how to interface the 850 port to the robot, but you could skip
the 850 and drive the robot directly (or via an inverter/buffer - SN7406?
SN7407?) from the 800's joystick ports.  They are driven by (if I remember
correctly) 2 6520 PIAs, so ports 0 and 1 provide 8 individually controllable
bits of control, and ports 2 and 3 provide 8 more.  A total of 16 bits which
can individually be set to be either inputs or outputs.