Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!seismo!rutgers!mit-eddie!uw-beaver!ubc-vision!alberta!auvax!rwa
From: rwa@auvax.UUCP (Ross Alexander)
Newsgroups: comp.sources.d,comp.emacs,comp.terminals
Subject: Re: 9600 baud problems (was Re: when using termcap, get it right!)
Message-ID: <191@auvax.UUCP>
Date: Mon, 15-Jun-87 21:02:17 EDT
Article-I.D.: auvax.191
Posted: Mon Jun 15 21:02:17 1987
Date-Received: Sun, 21-Jun-87 06:11:07 EDT
References: <1149@carthage.swatsun.UUCP> <8601@tekecs.TEK.COM> <6828@mimsy.UUCP> <6090@eddie.MIT.EDU>
Organization: Athabasca U., Alberta, Canada
Lines: 29
Keywords: termcap, curses
Summary: h19's considered harmful :-)
Xref: mnetor comp.sources.d:850 comp.emacs:1158 comp.terminals:312

In article <6090@eddie.MIT.EDU>, nathan@eddie.MIT.EDU (Nathan Glasser) writes:
> I had decided that the problem might be that the h19 couldn't really
> handle 9600 baud (as described above for the gigi), since it would
> explain most of the behavior I experienced, but it seemed a little too
> far fetched.  Since I thought h19's are/were fairly widely used, and
> regarded along with others like vt100's as a standard terminal type, I
> would expect it not to have such problems.
> 
> Does anybody know whether this is indeed true of h19's?

yes, it is indeed true.  the h19 firmware is, to put it tersely, sh*t.  OK,
that's a little strong - apologies to JGL (or whoever; I don't have my
source listings handy :-).  But the truth is that the ROM's are clunky, to
say the least.  They treat the z80 as though it was an 8080, for a start.

there are two fixes.  one is hardware; it is relatively simple to speed up the
clock on the z80 to 3 MHz and thereby pick up some speed.  i never had any
trouble with this on my h19 (part of my h89, actually).  the other is to
chuck the stock ROM's and replace them with something a little closer to
good code.  i borrowed a ROM from someone once that sped things up quite
a bit and also did pretty fair vt100 emulation (sans 132 column, of course)
but i can't remember the vendors name.  i will dig around a bit at home
and see what i can come up with.

btw, heath/zenith will sell you a listing of the ROM.  it is well commented
and very complete (i know 'cause i typed it in and assembled it, and then
hacked it up for my own use).

...!ihnp4!alberta!auvax!rwa	Ross Alexander, Athabasca University