Path: utzoo!attcan!uunet!tut.cis.ohio-state.edu!ucbvax!cleveland.Freenet.Edu!al423
From: al423@cleveland.Freenet.Edu (Don Burden)
Newsgroups: comp.sys.cbm
Subject: 2400 baud on C64
Message-ID: <9012130413.AA20937@cwns9.INS.CWRU.Edu>
Date: 13 Dec 90 04:13:18 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Reply-To: al423@cleveland.Freenet.Edu
Lines: 39



>
>I think you may run into some problems trying to use Kermit at 2400 baud.
>It won't be because of the RS232 routines if you have the patch.  But the
>80 column screen drivers are such that the screen scroll takes too much
>time, and it doesn't take long before the receive buffer overflows and data
>is lost.  This happens with Novaterm as well.  It's not possible to optimize
>the scrolling algorithm so it's fast enough to keep up.  What is needed is
>completely different screen drivers for 80 columns.  There is an effort being
>made to this end as we speak...
>
>-----------------------------------------------
>Nick Rossi, '93     | "That's nasty, Wyatt..."
>Harvey Mudd College | "That's Chet, Gary!"
>-----------------------------------------------

When I got my 2400 baud modem two years ago, I wrote my own term program
because no other term program I could find would work at 2400 baud on the
C64.  My program uses an 80 column bit-mapped screen and is fairly simple-
there's no up or downloading available and there is no VT-100 emulation,
but it does work reliably at 2400 baud.  This was written in 100% assembler.
The first version used a scrolling screen, but the 8000 bytes that has to 
be moved on every CR was just too much for the little 1 MHZ 6510 processor to
handle.  I just gave up on scrolling and tried homing the cursor after a
CR was received while on the 25th line.  When ready to print a new line, I
first erase the line so that text won't be overwritten.  The final result
looks quite good in my opinion, and is a lot easier to read.  I even use this
non-scrolling mode while reading text if connected to a system at 1200 baud.

About ANSI mode in Novaterm 9.1, I couldn't get it to work with a door 
program on a GT BBS.  The door program was BBS-Chess.  Also, on my C64,
Novaterm 9.1 keeps crashing after about 5 minutes when connected to a BBS
at 2400 baud.

--
Don Burden
New Albany, Indiana  USA
al423@cleveland.freenet.edu