MiSTer FPGA Forum

Do Tandy graphics work with the PCXT bios, or do I need to use the Tandy Bios?

No you need a Tandy Bios, the only one working is Tandy 1000 v101 for the moment.

I finally got a chance to really start to try this core last night in between painting issues with my arcade cabinet build. It is really awesome. I have it set up as Tandy. The only major issues I have so far is the very first video mode does not sync right on my TV. It looks like it could be a 40 column text mode from what I can see showing the 640k of memory. Once it gets to the screen where it shows the IDE stuff it is fine. Also after closing a program and returning to DOS it crashes with a panic about the memory and MCB chain. I was testing primarily with The Colonel's Bequest. I also tried some of the demos and saw a few screens with a few lines of graphics corruption but I think that is already known. I am using the FreeDOS hard drive. It doesn't seem to have a mouse driver. When I get more time, I will probably install MSDos and maybe my problems with crashing when returning to DOS will go away. I have the volume boosted 4x so I don't have to turn my TV up so much. Thanks again for the wonderful core.

thorr wrote: ↑Sat Nov 26, 2022 5:47 pm I finally got a chance to really start to try this core last night in between painting issues with my arcade cabinet build. It is really awesome. I have it set up as Tandy. The only major issues I have so far is the very first video mode does not sync right on my TV. It looks like it could be a 40 column text mode from what I can see showing the 640k of memory. Once it gets to the screen where it shows the IDE stuff it is fine. Also after closing a program and returning to DOS it crashes with a panic about the memory and MCB chain. I was testing primarily with The Colonel's Bequest. I also tried some of the demos and saw a few screens with a few lines of graphics corruption but I think that is already known. I am using the FreeDOS hard drive. It doesn't seem to have a mouse driver. When I get more time, I will probably install MSDos and maybe my problems with crashing when returning to DOS will go away. I have the volume boosted 4x so I don't have to turn my TV up so much. Thanks again for the wonderful core.

That crash is consistent and something I have been working in the background. I can duplicate with even a basic program that instantiates the Tandy Graphics mode, also in Indy 500, Keen 4 TGA, Eye of the Beholder, etc. Seems to be some conflict with UMB, apps loaded into high, and then something specific to the Tandy bios. With my exact same image I cannot replicate the crashes across IBM 5160, JukoST, micro8088 and GLABIOS_0.2.0_8T, though obviously those dont have Tandy modes so the games I am tested are showing in CGA. Also the same game using the Tandy bios but launched in CGA also work fine.

you can load the TSR HBREAK into memory which will let you ctrl-alt-c out of any game, but that is a bandaid. Note, this issue above seems to happen on real hardware when combined with UMB, DOSMAX, and Tandy bios. There is a thread on VCf that I spun back up looking for advice.

This will slow progress significantly for a plug and play curated image for Tandy Graphics + Adlib/CMS/Tandy 3-voice games. We are trying to script around those games that have this issue. If you do run into it, you can usually reboot-bypass all config.sys and autoexec.bat by holding shift before the starting MS/PC-DOS screens and the game will exit correctly. You can also not load DOS into High or any other UMBs and it will also work fine.

In my case, I need a LOT of applications running in high to make a curated image so there is enough free low mem: NANSI, DOS and shell, ctmouse, xprt, lfndos, doskey, hbreak, and then mymenu swapping to EMS. The good news is this all works fine in the other bios files so I can focus on CGA games for now.

flynnsbit wrote: ↑Sat Nov 26, 2022 6:53 pm You can also not load DOS into High or any other UMBs and it will also work fine.

Thanks! That is all great information. I suspected it might be a Tandy mode issue, and since it also happens on real hardware, there is nothing to fix in the core. Do you know if it also crashes with real MSDOS? You could perhaps make different HD images with different configs, or you could ask the question at the beginning if the user plans to use Tandy Graphics and if so, act accordingly when loading stuff, trying to minimize memory usage.

thorr wrote: ↑Sat Nov 26, 2022 7:06 pm

flynnsbit wrote: ↑Sat Nov 26, 2022 6:53 pm You can also not load DOS into High or any other UMBs and it will also work fine.

Thanks! That is all great information. I suspected it might be a Tandy mode issue, and since it also happens on real hardware, there is nothing to fix in the core. Do you know if it also crashes with real MSDOS? You could perhaps make different HD images with different configs, or you could ask the question at the beginning if the user plans to use Tandy Graphics and if so, act accordingly when loading stuff, trying to minimize memory usage.

Yup, tested across PC-DOS 2000 and MS DOS 6.22

I planned two VHDS, 1 focused on IBM PC generic CGA games and 1 focused on Tandy 1000/PCjr games. I have about 20 games that I am trying to get working with MyMenu reliably, then can expand that. It's been a rough go, these old systems were expecting crashes and ctrl-alt-del or even games that just booted from A: only so there is a bit of drama around making them work consistently from a frontend like MyMenu.

I should just do a CGA image first, but seeing the Tandy graphics and sound running on MiSTer is a driving force for me as I do have an original IBM PCjr that is one of my favorite systems.

Yeah, I am sure it is a huge challenge trying to work around everyone's software bugs. I had another thought too. You could ask at the beginning about Tandy or CGA, and present two different lists of games all within the same image, or break it out even further with more options and different lists of games presented. You could even list the games that go with each menu option at the beginning so people know which one they should choose. Just some ideas in case they help. You could also have a text message before the game starts that says "This game crashes at the end and requires a reboot."

Spark doesn't have a patreon, but I feel he deserves some coffees
https://ko-fi.com/spark2k06

I would post kitune-san as well but I don't know if he has one.

The area5150 demo has many timing mismatches with the edge centring that was carried out in this commit:

https://github.com/MiSTer-devel/PCXT_Mi ... 7a2c6106f6

I've done a work-around to avoid this, which would correspond to cases where the h_syncwidth variable is not standard for the usual video modes:

https://github.com/MiSTer-devel/PCXT_Mi ... b4e442909e

For the moment, in pre-release mode. Binary attached