SVI-707 Floppy Disk Images and/or CPM Utilites

Master (134)

01-03-2016, 07:06

I have just received a SVI-707 drive (from Bas - thanks) that I am hoping to use with my SVI-728 and Megaflash ROM SCC+ cartridge to be able to read the data from my original (SVI-318/328) Spectravideo formatted disks.
I was actually able to do that back in the day, and it's how I transferred the source of my games to convert them to MSX in the first place.
But none of my Super Expander(s) and drives work with an original SVI-318/328, so I am down to this option.
These disk images and utilities where available on Spectravideo.org, in a sub directory. The site is still up, but the files are no longer available for download. In addition Tomas has not been contactable for some time (I hope he is well).
I was wondering whether anyone else had these disk images or perhaps could suggest another solution I could try.
Regards
Tony

By Manuel

Ascended (19469)

08-04-2016, 22:05

Anyone? Because I'm also interested in them, as I'm trying to get it emulated.

By NYYRIKKI

Enlighted (6067)

08-04-2016, 22:15

Count me in... I'm also interested about reading / writing SVI-328 disks.

By Manuel

Ascended (19469)

09-04-2016, 00:01

Check this too, under SVI-728: http://msx.hansotten.com/index.php?page=svi-328

Did someone ever dump the CP/M ROM from the SVI-707?

By Manuel

Ascended (19469)

09-04-2016, 09:23

So, does someone know how the SVI-707 works anyway? It seems there are 2 ROMs, and you can select them by writing to address 0x7FBE (for the CP/M ROM) and 0x7FBF (for the MSX-DOS ROM). But according to the manual of the 707, booting with the CP/M disk will just load CP/M. But how is the switch of the ROM triggered then? When booting with the standard MSX-DOS ROM, the CP/M disk will be ignored, so there's nothing that triggers the switch to the CP/M ROM.

By gdx

Enlighted (6219)

09-04-2016, 10:41

tcruise wrote:

I was wondering whether anyone else had these disk images or perhaps could suggest another solution I could try.

I think the issue is the floppy disks format. The SVI-707 uses 320KB disks. Usually on MSX it is 360K or 720 KB. You need software that adapts to the number of tracks on the disk.

By mars2000you

Enlighted (6492)

09-04-2016, 15:33

Follow these links :

http://www.bluemsx.com/rel_download/SVI728/Svi728SystemDisks...

http://www.bluemsx.com/rel_download/SVI728/svi707msx.rom

http://www.bluemsx.com/rel_download/SVI728/svi707cpm.rom

http://www.bluemsx.com/rel_download/SVI728/Svi728Cpm.png

The format size of the SVI-707 disk seems to be 340kB. (note that 168kB and 338kB disks are used by SVI-318/328 with disk drive)

Additionnal infos from Tomas Karlsson:

case 0x3fbe: // Set CP/M boot
case 0x3fbf: // Set MSX DOS

- Nothing is ever read from the ports.

- The CP/M boot ROM should perhaps be first, it's the only one that writes to the selection ports $7FBE (CP/M) and $7FBF (MSX).

- It's unclear if the values written to the ports also used for decoding.

- Loading two 16KB or one 32KB and map them should be enough.

The CP/M 2.24 release 1.30 has a utility callled GOMSX that switches in the MSX ROM.

Booting with CP/M is made with a CP/M disk. From CP/M, you can switch to MSX-DOS with the utility GOMSX. It's not possible to directly boot in MSX-DOS.

Also it seems important to wait for the Disk BASIC to load before inserting the MSX-DOS disk image.

By mars2000you

Enlighted (6492)

09-04-2016, 17:35

Quote:

It's not possible to directly boot in MSX-DOS.

Precision: at least in the beta versions of blueMSX I've tested. But according to the SVI-707 manual, it should work. So the problem is to correctly implement the relation and the priority between both roms.

Quote:

Also it seems important to wait for the Disk BASIC to load before inserting the MSX-DOS disk image.

Then use poke &hf346,1:_system.

Again, here, to make it working, the FDC needs to be correctly emulated, it seems to be closer to a National FDC (MB8877A) than to the SVI-738 FDC, at least for this trick.

By l_oliveira

Hero (534)

09-04-2016, 18:28

MB8877A(Fujitsu, not National Semiconductor) is seen on software side as a WDC WD1793/WD2793.

By mars2000you

Enlighted (6492)

09-04-2016, 18:45

l_oliveira wrote:

MB8877A(Fujitsu, not National Semiconductor) is seen on software side as a WDC WD1793/WD2793.

In blueMSX, it's named as National FDC because it's mainly used in National machines, but that's indeed a variant of WDC WD1793/WD2793. Similarly, blueMSX speaks about Philips FDC, Microsol FDC, SVI-738 FDC and Panasonic FDC.

By Manuel

Ascended (19469)

09-04-2016, 18:57

It's a misconception mostly. There are only 2 types of FDC, the WD2793 and the TC8566AF. The variations for the former is caused by how all manufacturers mapped the FDC into the MSX RAM. As far as I can see it's unique for the SVI-707 (and documented in the service manual of the 728).