[MAME] Emulating the MTX

[Dave]

Hi,

That’s good work!

I thought that I would have dumped the SDX 80 column card ROMs, but it appears not. I will do it next week.

You could just copy files to and from the RAM disk to test it?

I don’t know of any Memotech MTX (or CP/M) software that actually pages >64k

Regards
Dave

[Pernod]

I thought that I would have dumped the SDX 80 column card ROMs, but it appears not. I will do it next week.

Thanks, that would be really useful.

You could just copy files to and from the RAM disk to test it?

But I need to format it first. Looks like multiple formatters on the SDX CP/M System Disk, FORMAT, FRMSDX, and SIDFMT. Tried SIDFMT F: and asks Type CR to go ahead, then nothing. I'm not seeing any IO in &50-&5F which is where I believe it should be accessed?

[Martin A]

You'll probably want Andy's REFORMAT.COM. It works with pretty much all the drive types.

[Bill B]

F: is usually a RAM disk not a Silicon Disk. It uses the pages above 64K on the MTX. So you should see activity on the page port (0x00) not on the Silicon Disk I/O ports. SIDISC formats both RAM disk and Silicon disks.

[Pernod]

F: is usually a RAM disk not a Silicon Disk. It uses the pages above 64K on the MTX.

Of course, the clue was in my previous screenshot "F: is type 51 - 512Kb RAM disc". Managed to format F:, copy over the SDX System Disk, and run NewWord from it, so looks good.

So how do I configure the Silicon Disc? Tried CONFIG F:41 but gave ERROR and CONFIGURATION ABORTED!

[Martin A]

Silicon discs have a driver - SIDISC.COM that needs to be loaded first.

It's not compatible with Andy's RAM disc code though, they both use the same drive letters and high memory.

There's 2 copies in the ZIP along with a re-built source that formed the basis of the SiDisc drive built into the CFX 2 boot rom.

I can't remember which one was the one that worked though, maybe even both work.

SIDISC.ZIP

(15.18 KiB) Downloaded 1493 times

[Pernod]

I thought that I would have dumped the SDX 80 column card ROMs, but it appears not. I will do it next week.

Any movement on this?

I'm also looking for any original SDX ROM dumps, not remakes as used in MEMU. The only one I can be sure of is the CP/M ROM from http://www.primrosebank.net/computers/m ... 12roms.htm.

I had previously not realised the SDX 512K was effectively a RAM expansion board, and incorrectly assumed it was only accessible through the Silicon Disc ports.

[1024MAK]

http://www.primrosebank.net is Dave’s site

Mark

[Pernod]

MAME now supports loading software from WAVs, and the majority of games from http://www.mtxworld.dk/download.php are working.

There are a couple that hang after loading, namely Pac-Man and Zombie Near. With Pac-man it loads, decodes, fills screen with game font/text/chars then gets stuck in an infinite loop:

Code: Select all

82DA jp $82DA

With Zombie Near it loads and gets to the 'A Game By' screen then hits a wait.

In both cases I'm guessing it's waiting for an interrupt but have no idea why they don't progress. Anyone have any thoughts on what maybe missing from the emulation?

[Bill B]

I have also implemented loading software from WAV files in MEMU http://primrosebank.net/computers/rpi/p ... memupi.htm.

One issue with this has been noticed. As you probably know, the sound of the tape loading does not come directly from the tape, but is faked using the sound chip. Sometimes, after completing loading, the sound chip continues to produce a tone, and does not stop until something else turns it off (typing <Ctrl+G>, or the loaded program producing a sound).

Is this something you have experienced with your MAME implementation? It is so long ago that I last loaded a real tape into my MTX that I don't remember whether it happened there.

Reviewing the ROM listing, it is not obvious that anything turns the sound off on completing loading.