Great clues. Thanks.
On Wednesday, July 22, 2020, 02:29:39 PM EDT, Jeffrey Birt
<bir...@soigeneris.com> wrote:
This loss of an entire block is the symptom of a missing chip select. When the
LCD driver chips are powered/reset they will drive every pixel on/black. When
they receive the proper initialization, they will drive every pixel off/clear.
It seems the rest and initialization steps are being done so commands are
getting through (and the machine is booting so the LCD has to be initializing
and responding).
Each driver chip on the LCD controls one block of pixels. If an entire block is
missing, it is a good sign the chip select is not getting through. It could be
a bad trace on the M100, a bad LCD cable or a bad LCD itself. If you have a
scope of logic probe you can check to see if all the chip select lines are
toggling.
Jeff BIrt
From: M100 <m100-boun...@lists.bitchin100.com> On Behalf Of Chris Fezzler
Sent: Wednesday, July 22, 2020 11:26 AM
To: m...@bitchin100.com
Subject: Re: [M100] Listserv Search
Here you go.
On Wednesday, July 22, 2020, 11:52:23 AM EDT, Stephen Adolph
<twospru...@gmail.com> wrote:
a pic of the garbled screen would be great if you can do it.. thanks
On Wed, Jul 22, 2020 at 11:37 AM Chris Fezzler <fezz...@yahoo.com> wrote:
Sorry - typing too fast. Top four lines of the screen.
Yes, mostly garbage all of the time. Except a hard rest will generate a proper
menu screen.
Yes, in BASIC the same. But if I type in a test program and hit RUN the
program will indeed run.
So the computer is getting the commands/keystrokes. Just not displaying bottom
four lines.
I think it is a component issue.
On Wednesday, July 22, 2020, 09:20:53 AM EDT, Stephen Adolph
<twospru...@gmail.com> wrote:
Hi Chris,
What do you mean by "the top 4". Do you mean top 4 lines on the screen? I
think so.
So is it correct to say that the LCD bottom 4 lines display garbage at certain
times
* not after a (hard) reset - you get a correct MENU display (not just a RESET
but a HARD RESET?)
* when you enter BASIC and/or run any software, the LCD bottom half shows
garbage?
I would suggest that you run a memory test.
I doubt that you have a fundamental problem with the LCD system, nor the
keyboard system.
good problem!
On Wed, Jul 22, 2020 at 9:02 AM Chris Fezzler <fezz...@yahoo.com> wrote:
I'm trying to troubleshoot what components on the circuit board process
keystrokes and send them to the screen.
The screen and keyboard on my Model 100 are in perfect working order. But only
the top four are processing correctly.
The bottom four are displaying gibberish. But if I type commands in BASIC,
they work. So again, not the keyboard or
screen but components that process the bottom half. A hard rest will present a
perfect menu screen. But upon entering
an app, the bottom four lines are not getting proper signal.
Sorry, I'm not an electronics or computer engineer. Just a hobbyist with a
soldering iron and a willingness to learn.
Plan to look at Technical Reference Manual to see if I can troubleshoot.
On Wednesday, July 22, 2020, 01:15:25 AM EDT, John R. Hogerhuis
<jho...@pobox.com> wrote:
On Tue, Jul 21, 2020 at 5:08 PM Chris Fezzler <fezz...@yahoo.com> wrote:
Is there a way to search old Listserv messages so I can research before
embarrass...err...I mean ask a dumb question.
Seriously, would like to research.
How old are we talking?
Gmane was our archive until it went down for a long time. Then it was back up
recently but only accessible through nntp readers. Not sure the status of that.
Our GNU Mailman list itself has an archive which goes back to 2011 when I took
over running the list.
http://lists.bitchin100.com/private.cgi/m100-bitchin100.com/
Or just ask. We Are The Archive.
-- John.
