MiSTer FPGA Forum

Thanks for the info. I'm still rooting for ya!

Is this still being worked on? It would be amazing to have PC98 simulation!

I'm proceeding very slowly.
Rewriting to ao486 base is very difficult, so I'm thinking of going with Zet base as before, but since the BIOS image for 8086 / V30 machine is very difficult to obtain, I think that there is no choice but to write a compatible BIOS. I have.
In that case, it seems that even DOS applications use the internal code of ROM BASIC, so it seems to be important how compatible the BIOS is created.
I have never written a program that handles segments, so I am doing trial and error, including how to write it in assembler.

thank you puu.

Thank you!
Would this be of help https://retro-type.com/PC98/files/PC98D ... _10Mhz.zip?

Thank you.
I tried tracing with the 98DO BIOS, but I used the OUTSB instruction at a very early stage in the BIOS, which seems to be an instruction added after 80186/80286 / V30, but in Zet this is executed Unable, exception 06: It seems that an undefined instruction has occurred. (I think exception 06 was reserved on 8086) It doesn't seem to work as it is.
However, it is predicted that it will not be so difficult to modify Zet (CPU core) to support OUTSB instructions, so I am thinking about proceeding with this method.

I'm thinking you could maybe make a 8086 that supports some of the 286+ instructions not related to protected mode? It would certainly allow a larger variety of programs to run too (programs compiled for 286+ that don't use its features but compiler optimizations make them use those instructions).
Is GDC working? Is there possibility of GRCG (not EGC) features?

This is the progress at the moment:
The INS and OUTS instructions that are missing in the 80286's real mode base have been added, and it seems that the INS instruction is not used in the BIOS, so it has been confirmed that the OUTS instruction works normally. The PUSHA and POPA instructions were implemented, but we found a bug and fixed it. As a result, the microcode has been expanded from 9-bit addresses to 10-bit addresses, so it is possible to increase the number of instructions to just under twice.
In GDC, the dot, line, and square drawing circuits are working for the time being. Circles and arcs have not been implemented yet. GRCG is also implemented.
Since I haven't connected the FDC yet, I can only boot ROM BASIC, but it is at the stage where ROM BASIC can be booted. Therefore, I think that development will proceed because the IO port can be accessed freely.

By the way, the development environment is DE0-CV. I will not port it to MiSTer until it is a little more complete.

Amazing project puu! Would it be possible to keep a 24 Khz option for those of us that still use old school MultiSync monitors?

sorry. The timing is adjusted to VGA (640x480) that can be used by the overwhelming majority of people.
The original (640x400) should be compatible with a slight change in RTL, but I have already thrown away the compatible display so I can't confirm it.

No problem, it appears to be the most reasonable decision. At least now I have a reason to get a real pc98

Awesome program puu! What's left to get working? Can't wait till it's out!

The PC-98 core port to MiSTer has been completed and is being uploaded.
There are some strange parts and functions that are not supported (pallet, HDD, etc.).

http://fpga8801.seesaa.net/archives/20210107-1.html

OK. Thank You very much puu.
Let's take a look ! Thanks for your work.

wow, that's incredible. Congrats!
Does zet itself port to Mister could be also used for normal PC games?

Since Zet SOC itself is compatible with IBM PC, I think ao486 has higher performance. I think it's better to use ao486 than to port Zet to MiSTer.
I only use the core part of Zet (i8086).

puu wrote: ↑Thu Jan 07, 2021 1:40 am The PC-98 core port to MiSTer has been completed and is being uploaded.
There are some strange parts and functions that are not supported (pallet, HDD, etc.).

http://fpga8801.seesaa.net/archives/20210107-1.html

Hello

Thank You so much Mister Puu

I tried quickly this morning.
I created a boot.rom file but the core does'nt start and the MiSTer is unresponsive.

I have tried the core and only got a beautiful black screen. The MiSTer hangs up and a total reset must be done. I don't know if it's a problem with the ROM or if the core itself has a fault.
No OSD present and can't do anything else. Does the video work over HDMI or VGA?, I am not very clear about it, because the MiSTer hangs, maybe it could be a problem when synthesizing.

I have resynthesized the core and we are the same. No success and too many warnings. It still does not work and the MiSTer hangs completely.

It seems to be a problem with clocks and their allocations/associations.

Ok, I am resynthesizing and I have realized that you have to choose the Zet98MiSTer project.
In a while when I finish synthesizing I will tell you if it is specifically this. I was generating a release-Zet98MiSTer.rbf when it is the Zet98MiSTer.rbf to generate.

Edit:

Unfortunately I have obtained the same result, the behavior is the same. It does not work.

I put the compiled .rbf in output_files / and updated it to the archived one, so please check there.

puu wrote: ↑Thu Jan 07, 2021 2:09 pm I put the compiled .rbf in output_files / and updated it to the archived one, so please check there.

I don't see it.

It's good, the output folder is there now.
I will test.

it's better!
But no osd menu


I recompiled, same issue

hi
where can we take the rbf please ?

breiztiger wrote: ↑Thu Jan 07, 2021 3:09 pm hi
where can we take the rbf please ?

voilà !!

merci !!!

tontonkaloun wrote: ↑Thu Jan 07, 2021 2:44 pm It's good, the output folder is there now.
I will test.

Same for me. Exactly the same. But it doesn't start/work.

If you don't have Quartus, you can use this to extract qar files: https://github.com/makigumo/unqar/blob/master/unqar.py (you need Python).

Is the menu displayed when you press F12?
If the menu is displayed, the core itself should be running.
Since Zet is equivalent to 8086 / V30 / 80186, the BIOS of the model at that time is required. As for the era, if it is not the BIOS of the era of PC-9801VM and PC-98DO, the instructions related to protected mode are used in the BIOS and it will not start.