Re: [M100] Looking for TRS-80 Catalog Item 26-3612

The serial port adapter looks quite a beast internally. http://www.pc-1500.info/Data/Service_Manuals/CE-158_Service_manual.pdf The CE-158 is the Sharp interface from which the 26-3612 was derived, the parallel port was removed(?). Seems it includes a ROM, serial I/F chip as well as a processor.

Re: [M100] memory corruption on power cycle?

Have you tried running a RAM tester? There are a few in the archive: http://www.club100.org/library/libutl.html I have used both RAMCHK.BA and RAMTST.BA to find bad RAM modules. Although if the bad RAM

Re: [M100] LCD Lines

I have not had any success removing the LCD bezel so would not recommend that approach. It was hard for me to get the elastomer strip to re-conform on the PCB making things worse in the end. I tried it on two different LCDs so perhaps I need more practice :) One trick that works for me is to

Re: [M100] sending fast data using modified cassette port

The smallest number of parts I have so far found is runCPM (https://github.com/kklis/RunCPM) on a Teensy 3.5 or 3.6. It is an emulated version of CP/M V2.2 (uses a Z80 emulation) but it can be compiled on the ubiquitous Arduino IDE. Of course it can also be run on quite a few other platforms.

Re: [M100] Using a US DVI unit in the UK

: [M100] Using a US DVI unit in the UK > Would it effect the 50 / 60 hz frequency issue? > > > > Sent from my iPad > >> On 16 Feb 2020, at 6:38 am, B4 Me100 wrote: >> >>  >> That should work. Although I would probably enclose it to prevent >>

Re: [M100] Using a US DVI unit in the UK

The cleanest solution might be to buy a packaged autotransformer. This could be hidden under the desk and be available if you buy any other 110V kit :) Something greater than 100W would be fine for the DVI. RS have quite a few autotransformers:

Re: [M100] Using a US DVI unit in the UK

That should work. Although I would probably enclose it to prevent accidentally touching the 240/110V. From: M100 on behalf of James Zeun Reply-To: Date: Sunday, February 16, 2020 at 1:03 AM To: Subject: Re: [M100] Using a US DVI unit in the UK > I know little about power supplies, but

Re: [M100] Starblaze 100 strange behavior on select LCDs

Actually a very good guess! I had the same problem with Starblaze on a few screens so decided to investigate the annoying behavior after finding this thread. Looking at the code that writes to the screen it is really badly implemented. When updating the screen it sends an LCD command to set

Re: [M100] Using a US DVI unit in the UK

; > >>> > In actual practice this has never happened to me, and I've migrated to the >>> 50Hz world from the US. I even run a Sears table saw with its 60Hz motor on >>> 50Hz (OK, it turns a bit slower) and figured I would just buy a new motor >>> (may

Re: [M100] Using a US DVI unit in the UK

With such a cheap transformer in the DVI the 50Hz should not really produce much of an impact, the output voltage might be down slightly but I doubt the internal transformer is that well tuned to 60Hz. I would be more worried about failure of parts due to their age, especially the caps. On

Re: [M100] Using a US DVI unit in the UK

You will need a 240VAC to 110VAC autotransformer to run the DVI. Probably an adapter for the TV too, need to convert the composite output to UK standards. Unless you have a universal input monitor to use. The units are regionally specific. From: M100 on behalf of James Zeun Reply-To:

Re: [M100] Ultimate Rom II TS-Dos

The attached file will generate TSLOAD. Quite a small Basic program that loads the file into memory, the .do file can be deleted after loading. On 10/3/20, 8:47 PM, "M100 on behalf of Joshua O'Keefe" wrote: >On Mar 10, 2020, at 8:39 PM, Kurt McCullum wrote: >> TS-DOS and Sardine for UR-II

Re: [M100] VirtualT support for REXCPM hardware

The 8085 instruction extension looks an interesting addition. I created a Teensy 3.6 emulation of the 100 which has 165KB RAM available and was working on a bank switching scheme. I had thought of creating my own bank switch instruction but extending the address range would be an alternative -

Re: [M100] T-102 is here!

The attached file will generate TSLOAD for the M100/102. There should be one for the 200 but I do not have that file. From: M100 on behalf of Tom Wilson Reply-To: Date: Friday, March 13, 2020 at 11:33 PM To: M100 Mailing List Subject: Re: [M100] T-102 is here! > I can't seem to find

Re: [M100] DVI cable length

You may want to take a look at the http://www.club100.org/library/libdrv.html archive. It has a few programs that seem to swap the DVI and TS-DOS. I have not used any of them but there might be something of use? From: M100 on behalf of Reply-To: Date: Saturday, March 14, 2020 at 2:22 AM

Re: [M100] Astronomy programs

There are a couple sort of mixed into the utilities archive on Club100 http://www.club100.org/library/libedu.html might not be very interesting though. - Convert ALT-AZ to Equitorial coordinates for a telescope and visa versa. - A program to display azimuth and altitude of the sun for date,

Re: [M100] REX on M200

Yes just needs to be re-flashed and it should be fine. It is probably the easiest way to get TS-DOS onto the machine. There are a few options to build an EEPROM board eg http://tandy.wiki/Teeprom but if you already have a REX then I would just go that route. From: M100 on behalf of Tom

Re: [M100] Video adapter.

The 25th line is used either as the label line or a regular line on the DVI screen, similar to that used on the LCD panel. Esc T turns on the line and Esc U turns it off if I recall correctly. I ended up using the 36th line for status information such as memory free etc or file info. Works out

Re: [M100] Video adapter.

Speaking of video adapters has anyone used the Œnewish' Arduino MKR Vidor 4000, it comes with an FPGA and ARM processor. From the YT videos it looks like it can be configured to drive HDMI and leave quite a few pins free for serial ports and digital IO. It also comes with a built in WiFi. The

Re: [M100] Missing ROM elements

; 0> > > > It's reshared. Stupid me. > > > > > > On 4/10/20 9:15 PM, B4 Me100 wrote: > > >> >> The link takes me to a login screen? Is there part of the link missing. >> >> >> >> >> From: M100 on behalf

Re: [M100] Missing ROM elements

This looks like the old oxidation of the contacts problem for the screen. It is not a cable problem otherwise the rest of the screen would be faulty. The trick I personally use is to take a piece of thin-ish card and slide it very, very, very gently along the elastomer material that connects the

Re: [M100] Missing ROM elements

gt; > Meanwhile I have a 200 incoming that I look forward in using. It may suit my > targeted needs more so than the 100. I have plans for the 100 though, once i > can see the entire screen. > > > On 4/11/20 8:06 AM, B4 Me100 wrote: > > >> >> T

Re: [M100] Missing ROM elements

Generally it has worked for me but perhaps the corrosion on the screen is just be too much the PCBs in the M100/102s use the cheapest consumer materials and sometimes leaking batteries, residual flux or bad storage can lead to corrosion problems which stops the screen working (as well as the rest

Re: [M100] YouTube Vids BIRT!

Model III On 14/4/20, 5:05 AM, "M100 on behalf of me" wrote: >An old tv movie from the early 80s. if you go to 1:10, it'll show a >TRS-80. Anyone know which model it is? I'd venture a 4 but the keys >don't look right.

Re: [M100] Missing ROM elements

The link takes me to a login screen? Is there part of the link missing. From: M100 on behalf of me Reply-To: Date: Friday, April 10, 2020 at 4:38 PM To: Subject: Re: [M100] Missing ROM elements > > > > https://www.omgwtflol.net/nextcloud/index.php/f/108057 >

Re: [M100] T-102 is here!

If I recall that is reasonable charge level, but with only ~200-400uA drain it could stay there for quite a while.The standby current is ~50uA @ 3.0V or ~100uA @ 5.5V for the 8Kx8 SRAMs. From: M100 on behalf of Tom Wilson Reply-To: Date: Friday, March 13, 2020 at 9:50 AM To:

Re: [M100] NiMH Batteries

That is a neat/cheap solution I shall have to try that next time. From: M100 on behalf of Mike Stein Reply-To: Date: Friday, March 13, 2020 at 9:45 AM To: Subject: Re: [M100] NiMH Batteries > I replace mine with cordless phone batteries from the local Dollar Store: >

Re: [M100] T-102 is here!

Congratulations! Welcome to the Model T102 owners club :) >From the motherboard pic the battery looks like an original Yusa I doubt it has been replaced. At 4.3V it is bad it should be around 3.7V when off to allow the SRAM to drop into their lowest standby current. As Josh would say it should

Re: [M100] WiModem TPDD

I don¹t think TPDD uses hardware handshaking it relies on delay loops. The TPDD drive generates DSR to indicate there is something present which is required by the ROM drivers. When I tried it via an ESP12 to LaddieAlpha the big issue was the variable delay even with a modified TPDD I could not

Re: [M100] Just got my 100

Part of the fun is fixing the 100:) It sounds like it just needs a tune upS. Couple of things to look at are the internal NiCd (most likely dead) and some of the caps have possibly failed. There are a few great videos on YouTube on how to replace both the NiCd and re-cap the board. This

Re: [M100] Just got my 100

There are a few folks on the list that sometimes will repair units, they might be able to offer more hands on help - although with the current situation that might be difficult. On 1/4/20, 12:40 PM, "M100 on behalf of me" wrote: > >I have never soldered a thing in my life. Nor have I ever

Re: [M100] Just got my 100

I agree nothing like trying and learning. As they say Slow is Pro. I would do one cap at a time and check underneath each cap to clean up any mess left due to leakage. Try not to heat the traces too much the boards are really cheap and low quality, lifting a track is quite a possibility with

Re: [M100] CCR-82

While looking for an original cable you could make your own, the M100 Manual (pg 207) has the pin outs for the connector. The cables use 3.5mm plugs for the TX and RX and 2.5mm for the remote. A post in this list provides the schematic

Re: [M100] CCR-82

Here is a link to the service manual: https://colorcomputerarchive.com/repo/Documents/Manuals/Hardware/CCR-82%20S ervice%20Manual%20(Tandy).pdf On 24/4/20, 3:32 PM, "M100 on behalf of me" wrote: > >I just ordered this >

Re: [M100] C64 restoration and fresh mobos

The one I like is the ZX Spectrum Next https://www.specnext.com/ It is more of an update rework with a new case etc using FPGAs to replace just about all of the logic. The M100 has been done but not to the level of the C64, it uses a Teensy but has all the ports except the modem port. :)

Re: [M100] C64 restoration and fresh mobos

I do not have a link but if you have questions etc please feel free to contact me off list. From: M100 on behalf of Wayne Talbot Reply-To: Date: Thursday, May 7, 2020 at 7:10 AM To: Subject: Re: [M100] C64 restoration and fresh mobos > I would be interested in knowing more about the

[M100] M100/T102 diagnostic harness

Just shared 3 PCBs on OSHPark for an M100/T102 diagnostic harness set that I have been using to repair a few model T¹s and keep others alive. Since I found the method to be quite beneficial I thought others might be interested. If you are familiar with the C64 diagnostic harness it is the the

Re: [M100] M100/T102 diagnostic harness

Just responded directly to your email :) From: M100 on behalf of Jeffrey Birt Reply-To: Date: Thursday, May 7, 2020 at 3:43 PM To: Subject: Re: [M100] M100/T102 diagnostic harness > > Would you want to swap for a M100 diagnostic PCB set? > > I feel a diagnostic update video coming

Re: [M100] Cassette

A couple of things: 1. You may need to play with the volume at least on the M100s setting the volume correctly is essential. I usually find it has to be set quite high on my M100 machine. 2. The Header portion of the playback is required to detect the body of the data. That is the monotone at

Re: [M100] Scripsit 100?

You can try here, scroll down the Model 100 cassette wav images: http://www.classiccmp.org/cini/systems.htm The Scripsit one works, have not tried speculator. I used it to recover some old files :) From: M100 on behalf of r Gi Reply-To: Date: Friday, September 4, 2020 at 1:55 AM To:

Re: [M100] M100 Digest, Vol 117, Issue 6

I would check the two 10uF caps that sit on the -5V line in the analog section and replace - they always seem to be bad. There are two further ones on the +5V that should be replaced too. I would personally just replace all the electrolytic caps to eliminate them as a source of the problem. The

Re: [M100] EZ Assembler

n Friday, August 14, 2020, B4 Me100 wrote: >> If you take a look at the .asm produced by Ken Pettit: >> http://bitchin100.com/wiki/index.php?title=VT100#VT100_Driver >> <https://nam04.safelinks.protection.outlook.com/?url=http%3A%2F%2Fbitchin100. >> com%2Fwiki%2Findex

Re: [M100] EZ Assembler

If you take a look at the .asm produced by Ken Pettit: http://bitchin100.com/wiki/index.php?title=VT100#VT100_Driver There you will see "VT100 Source², the VT100.asm file within the .zip file provides some ideas on how to assemble a .co file directly from TASM sources. The important parts are

Re: [M100] PIC32MX (off topic but related!)

One problem I have found importing other projects is to make sure the versions of MPLAB and the XC32 compiler are identical. Not sure how old the VT100 project might be but MPLAB and its associated libraries have changed a lot, even the methods used to perform some operations have changed. The

Re: [M100] PIC32MX (off topic but related!)

One thing I forgotŠ If you are using the free/unlicensed version then there is no optimization. It could be the VT100 app was compiled with a licensed version of the compiler with some level of optimization. From: M100 on behalf of Ken Pettit Reply-To: Date: Saturday, July 18, 2020 at 2:22

Re: [M100] Narrowing down issue, I think

Unfortunately that is a pretty typical solder joint for an M100 it is OK. One thing you might want to look for is corrosion caused by flux residue that was left behind after the manufacturing process. It looks like a copper brown deposit but might hide a damaged track. I have worked on a few

Re: [M100] Hacking the expansion bus?

Historically there have been quite a few pieces of hardware designed for the expansion bus, especially for the M100. I have an 1990s version of a battery backed 128K SRAM bank that can be used to provide several banks of switchable memory. So the bus has not been totally ignored :) Two+ years

Re: [M100] M100 Digest, Vol 115, Issue 2

Very common problem ³generally" caused by bad electrolytic caps on the -5V output line. The -5V is used to provide the contrast voltage for the LCD so when it fails the screen will fade out. If you recap the board it should go some way to fixing the problem. It will also help the +5V line too

Re: [M100] M100 turns on briefly then fades away after a few seconds...

They sometimes look OK until you remove them and the leads fall off :) After 35years they are well past their life expectancy and are probably not performing anywhere close to their specs. Usually you can see visible corrosion around the area of the cap where they have outgassed and eaten into

Re: [M100] Tandy 200 Black Screen

Sounds like the cable for the screen might not be correctly inserted in the connector. You could revisit the cable and make sure it was not broken or cracked when the computer was re-assembled. The plastic ribbon cable is a bit tricky to re-insert. The black screen (if the boot process is

Re: [M100] Over active 'low battery' light

I think if you use rechargeable batteries you will be very close to the battery low threshold - it is not measured in a precision fashion just using a simple resistive voltage divider and a couple of transistors. With a 1.2V (nominal) battery this would give 4.8V at the terminals when fully

Re: [M100] PIC32MX

I have written quite a lot of code for the PIC32MX795 for use in my DVI and Micro-DVI boards. Please feel free to DM. Although I do hate MPLAB ­ X :) From: M100 on behalf of Stephen Adolph Reply-To: Date: Saturday, July 18, 2020 at 7:26 AM To: Subject: [M100] PIC32MX > anyone on the

Re: [M100] New Boards

your preferred supplier. On 17/12/20, 3:28 PM, "M100 on behalf of Josh Malone" wrote: >On Thu, Dec 17, 2020 at 6:23 PM B4 Me100 wrote: >> >> I took both options reliable and newer features using a Teensy 3.6 to >> provide the CPU power and interface versatil

Re: [M100] Model 100 Repair - Keyboard not responding, LCD missing a column

You might want to check you local ACE Hardware store I found they have Metric threaded machine screws that worked for me. Depending where you live of course :) From: M100 on behalf of Scott McDonnell Reply-To: Date: Sunday, December 20, 2020 at 5:06 PM To: "m...@bitchin100.com" Subject:

Re: [M100] Cassette file formats

Hi If you look at pg 212 of Oppendahls book, Inside the TRS-80 Model 100, there is a pretty reasonable description of the format. Quick summary: The bit frequencies are 2400Hz = 1 and 1200Hz = 0. The files consists of two or more blocks, the first block is header with 512 bytes of 55H (or AAH

Re: [M100] Model 100 Repair - Keyboard not responding, LCD missing a column

ub100 site and I have probably looked at > the thing I want a 100 times and just not recognizing it. Would really > appreciate a suggestion. > > Goodnight folks. Thank you for putting up with me tonight! > > Scott M. > > > From: B4 Me100 <mailto:b4me...@hotmail.c

Re: [M100] low profile pcb pins

I have used the following two strips with the M100 SysBus socket for quite a few projects - not sure it is the same format as the NEC socket. The strips are very low profile which means the modules easily clear the cover, even with tall components on the top side. But they are expensive which is

Re: [M100] Model 100 battery cover

Certainly interested if they are listed for sale. I was looking into trying to cast new ones that might be stronger, the printed ones are too weak as mentioned. The available plastic materials etc are getting better. From: M100 on behalf of Ken Pettit Reply-To: Date: Thursday, August 19,