Start OpenMSX with MSX-DOS support

Paladin (1002)

24-05-2022, 02:05

Hi,

In the MSXgl build tool, I allow the user to automatically launch his program after the build, with different emulators, including OpenMSX.
In the case of a program for MSX-DOS 1 or 2, I had a problem when the default machine had no disk controller and, for MSX-DOS 2, when it didn't have the DOS 2 kernel ROM or 128 KB of RAM.

I tried to play with the extensions to see if there was a "universal" configuration to launch these programs in any machine, and I came to these extension configurations:
- DOS 1: -exta slotexpander -ext Panasonic_FS-FD1A -ext ram64k -diska {path}
- DOS 2: -exta slotexpander -ext Panasonic_FS-FD1A -ext ram512k -ext msxdos2 -diska {path}

The DOS 1 configuration works on all tested MSXs (even a Canon V8 with 16K RAM).
On the other hand, the DOS 2 configration does not work on MSX 1 (it launches Disk-BASIC at best).

- Is it not possible to have a 128 KB+ RAM extension on MSX1?
- Is there a solution to use MSX-DOS 2 on an MSX1?
- Is there a more "standard" disk controller than the others? I took the FS FD1A because it's the first one I found that supports 720K FDD. ^^

By gdx

Enlighted (6210)

24-05-2022, 02:12

MSX-DOS 2 doesn't support the MSX1 computers. Use Nextor!

By sd_snatcher

Prophet (3659)

24-05-2022, 02:20

aoineko wrote:

- Is it not possible to have a 128 KB+ RAM extension on MSX1?

Yes, it's possible.

Quote:

- Is there a solution to use MSX-DOS 2 on an MSX1?

You can use Nextor, that's just a newer version of MSX-DOS2 with a fancy name.

You need to download the "Standalone ROM with ASCII 16 mapper" from this site.

Quote:

- Is there a more "standard" disk controller than the others? I took the FS FD1A because it's the first one I found that supports 720K FDD. ^^

No, but the opposite is true. The Microsol CDX2 and Talent TDC-600 are examples of "less standard than others".

But, anyway, if you need an MSX1 with a built-in 720KB floppy drive, I'd recommend you to use the National CF-3300. I had the impression that this machine was already the default MSX1 for some time now...

By MsxKun

Paragon (1124)

24-05-2022, 15:32

gdx wrote:

MSX-DOS 2 doesn't support the MSX1 computers. Use Nextor!

Wrong. You can use MSX-DOS2 on a MSX1 as long as you have an internal or external RAM mapper.

By MsxKun

Paragon (1124)

24-05-2022, 15:40

aoineko wrote:

- Is it not possible to have a 128 KB+ RAM extension on MSX1?

Totally possible with no problems. I had my Sony HB-20P using 4MB of RAM.

aoineko wrote:

- Is there a solution to use MSX-DOS 2 on an MSX1?

A RAM mapper. When I put my 4MB RAM card on the 20P I also used my CF-IDE interface with DOS2. All very fine. It's convenient to use FAT16 patch by Okei specially with Multimente I think MM itself needed another patch to show file size properly. of course, You need the DOS2 diskrom. I have Sunrise's CF-IDE and the LPE-MMC-SD both with DOS2.

aoineko wrote:

- Is there a more "standard" disk controller than the others? I took the FS FD1A because it's the first one I found that supports 720K FDD. ^^

On openMSX, as external drive, I plug the Sony HBD-F1 (or5?), wich works fine and also I own as real hardware.

By ducasp

Paladin (680)

24-05-2022, 16:53

The question about MSX1 and Mappers is always whether the mapper is able to initialize itself (i.e.: SDMAPPER) or not. If it is, it will work, if it is not, since MSX1 bios doesn't know mappers and do not initialize them, it won't work. Not sure how that applies to OpenMSX mappers and cartridges that would allow nextor to be used.

By MsxKun

Paragon (1124)

24-05-2022, 18:23

Well, you could execute a ROM cartridge before the DiskROM, that initializes the mapper, but we are starting to do some trickery here and abuse of slots That should not be a problem on OpenMSX tho. Used MSX1+DOS2 there, usually IDE-CF+normal 512k RAM mapper exts.

By Manuel

Ascended (19462)

24-05-2022, 22:14

openMSX has the intention to behave the same as the real hardware, and when I try a Sony HB-20P with a 512kB memory mapper and MSX-DOS2, Disk Basic is not started. So apparently DOS2 isn't working on that system. I also tried with the (emulated) ASCII MSX-DOS2 with built-in RAM extension.
When running on a 16kB MSX1, you do get to see 28815 bytes free, so the RAM is detected. But I guess the same segment is mapped to all pages (haven't checked that).

By MsxKun

Paragon (1124)

24-05-2022, 22:24

I never tried MSX-Basic, just MSX-DOS2 with the DOS prompt.

This is a really old pic, but I have the same setup, tho usually I used LPEMMC-SD instead of IDE

Btw, that's not my 20P, its a 10P, from Jon from Relevo, at a MSX Ru :) But, works the same.

By Manuel

Ascended (19462)

24-05-2022, 22:26

Ah, when I use the openMSX IDE extension + memory mapper on an MSX1, MSX-DOS2 does boot indeed Not sure why though, perhaps the emulated mapper initializes itself? And apparently your mapper did too?

By MsxKun

Paragon (1124)

24-05-2022, 22:40

Now I just tried this with openMSX, using an MSX1 Canon V-20 with IDE (for MSX-DOS2) and a 512k ram mapper.