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From: @RUTGERS.ARPA:prindle@nadc
Newsgroups: net.micro.cbm
Subject: re: 1200 baud on C64
Message-ID: <411@topaz.ARPA>
Date: Mon, 28-Jan-85 15:28:12 EST
Article-I.D.: topaz.411
Posted: Mon Jan 28 15:28:12 1985
Date-Received: Wed, 30-Jan-85 04:26:23 EST
Sender: daemon@topaz.ARPA
Organization: Rutgers Univ., New Brunswick, N.J.
Lines: 14

From: prindle@NADC

Running a 1200 baud modem on the C64 requires more than a little sorcery, I'm
afraid.  Simply plugging the value 8 into the baud rate register won't do
it.  You will appear to transmit fine, but blocks of data coming back will
surely be periodically damaged.  But reliable 1200 baud full duplex communi-
cation is definitely possible, just rather tricky.  Many early releases of
commercial telecom programs for the 64 (including Compuserve's VIDTEX) fell prey
to this trap.  The full solution is too complicated to explain here, but to put
you on the right track, try opening the RS-232 channel with the baud rate code
set to zero, and with two additional characters in the name equal to 60 and 1.
An equivalent in BASIC:	open 2,2,0,chr$(0)+chr$(0)+chr$(60)+chr$(1)
This will cure the fundamental problem - you may soon find some others; welcome
to the wonderful world of Commodore!