Re: [M100] 10.4" LCD with the Model 100
Sounds like an ambitious project ;-) You can send the display data out to a display via the com port and, if you need the port for something else, even the bar code port; there is also a terminal driver that is compatible with the M100's screen codes. Have a look here: https://bitchin100.com/wiki/index.php?title=VT100 On Wed, Nov 8, 2023 at 9:31 PM Scott McDonnell wrote: > I ended up with a small qty of 10.4" monochrome LCDs and was asking around > for ideas what to do with them. In one of my other groups, it was suggested > to get one working as a display for a model 100 and I thought that was a > great idea. Probably the most compatible way to do this would be to emulate > how the DVI worked, but I have never seen one in action. I have also gotten > confused looking up youtube demonstrations. In some, the DVI plugs into the > 40 pin expansion socket on the bottom. In another video, it was plugged > into the parallel port, I think. The 40 pin expansion makes more sense to > me. > > Looking through the service manual, it appears to use a 8255 PPI to > interface with the computer to write into VRAM and ARAM which a CRT > controller then uses to paint the screen on a monitor. Is that a simple > description of how it works? It appears to require loading a driver program > and is not something that is just available in the BIOS, right? Would it > work with all screen output, even graphics, etc? If so, maybe compatibility > is not really an issue with my own driver? > > So I am looking for links and info to help me on this quest. The service > manual is great, but it is geared more toward repair than theory of > operation. Is anyone aware of any reverse engineering information on this? > Has anyone attempted to duplicate it before? > > These displays are controller-less, so of course first I need to design a > controller for them. I was planning to just use a Raspberry Pi Pico to > drive it. > > Here is a really good project with tons of information on driving my exact > display for those curious which display it is. The display is nearly > exactly the size of the Model 100, so making an enclosure that could flip > down like a laptop would be possible. > > http://www.projekte.daleske.de/mcp/49_LCDM/LCDM.htm > >
Re: [M100] 10.4" LCD with the Model 100
" In some, the DVI plugs into the 40 pin expansion socket on the bottom. In another video, it was plugged into the parallel port, I think. The 40 pin expansion makes more sense to me." The TRS-80 Model 100 has its system bus expansion port on the bottom. The Tandy 102, the successor to the TRS-80 Model 100 has its expansion port on the back of the unit. The connector looks like a parallel port, but is not a parallel port. The Model 100 and Tandy 102 have a parallel port but the connector looks and is compatible with the internal parallel port to motherboard cable used in PCs. -- John.
[M100] 10.4" LCD with the Model 100
I ended up with a small qty of 10.4" monochrome LCDs and was asking around for ideas what to do with them. In one of my other groups, it was suggested to get one working as a display for a model 100 and I thought that was a great idea. Probably the most compatible way to do this would be to emulate how the DVI worked, but I have never seen one in action. I have also gotten confused looking up youtube demonstrations. In some, the DVI plugs into the 40 pin expansion socket on the bottom. In another video, it was plugged into the parallel port, I think. The 40 pin expansion makes more sense to me. Looking through the service manual, it appears to use a 8255 PPI to interface with the computer to write into VRAM and ARAM which a CRT controller then uses to paint the screen on a monitor. Is that a simple description of how it works? It appears to require loading a driver program and is not something that is just available in the BIOS, right? Would it work with all screen output, even graphics, etc? If so, maybe compatibility is not really an issue with my own driver? So I am looking for links and info to help me on this quest. The service manual is great, but it is geared more toward repair than theory of operation. Is anyone aware of any reverse engineering information on this? Has anyone attempted to duplicate it before? These displays are controller-less, so of course first I need to design a controller for them. I was planning to just use a Raspberry Pi Pico to drive it. Here is a really good project with tons of information on driving my exact display for those curious which display it is. The display is nearly exactly the size of the Model 100, so making an enclosure that could flip down like a laptop would be possible. http://www.projekte.daleske.de/mcp/49_LCDM/LCDM.htm
