MiSTer FPGA Forum

Hello everyone,

I found in my old original CDs, a C64+Spectrum CD called Retro Gold that I bought many years ago.
On this CD there are emulators (C64 & Spectrum for PC & Amiga) and a lot of games for those 2 systems.
My idea was to try the games on my Mister after having transfered all the disk images to my external SSD.
For the C64, there was no issue as the format of the disks is .D64 and so far, all the ones that I've tested ran fine.

For the Spectrum games, the story is different because the format of the images is .SNA and this format is not recognized by the Spectrum core.
Is one of you know if the .SNA format can be converted to another format compatible for the Spectrum core of the Mister ?
For information, here is the CD that I'm talking about.

Thank you in advance for your help/tips.

https://worldofspectrum.org/faq/referen ... s.htm#File

describes all the formats. Sna is a snapshot of the system

this converts sna into other formats

https://worldofspectrum.net/legacy-info/taper/

The core is able to run .sna files ("Load Snapshot *Z80, SNA" in OSD), I've just tried to load a few and they work ok. Did you try your snapshots in an emulator?

Thank you @FPGA64,
This is the tool that I was looking for.

@akeley,
Oh I missed this information, will double check this evening. Seems that I need new glasses
Thank you so much.

kathleen wrote: ↑Thu Jun 01, 2023 6:18 pm

Hello everyone,

I found in my old original CDs, a C64+Spectrum CD called Retro Gold that I bought many years ago.
On this CD there are emulators (C64 & Spectrum for PC & Amiga) and a lot of games for those 2 systems.
My idea was to try the games on my Mister after having transfered all the disk images to my external SSD.
For the C64, there was no issue as the format of the disks is .D64 and so far, all the ones that I've tested ran fine.

For the Spectrum games, the story is different because the format of the images is .SNA and this format is not recognized by the Spectrum core.
Is one of you know if the .SNA format can be converted to another format compatible for the Spectrum core of the Mister ?
For information, here is the CD that I'm talking about.

Thank you in advance for your help/tips.

RetroGold.JPG

As others already wrote the core supports SNA but I would avoid the format outside of software emulation. The SNA Format is just a snapshot of the Spectrum RAM no CPU registers are stored which makes SNA files prone to fail.
Furthermore SNA files should be used on the machine they were created for otherwise you can run into problems. There are also general problems with the SNA format, this page has an excellent explanation.

https://worldofspectrum.org/faq/reference/formats.htm

A better snapshot format for the Spectrum is Z80, here additional to the RAM all registers are saved:

https://worldofspectrum.org/faq/reference/z80format.htm

kathleen wrote: ↑Thu Jun 01, 2023 6:18 pm

Hello everyone,

I found in my old original CDs, a C64+Spectrum CD called Retro Gold that I bought many years ago.
On this CD there are emulators (C64 & Spectrum for PC & Amiga) and a lot of games for those 2 systems.
My idea was to try the games on my Mister after having transfered all the disk images to my external SSD.
For the C64, there was no issue as the format of the disks is .D64 and so far, all the ones that I've tested ran fine.

For the Spectrum games, the story is different because the format of the images is .SNA and this format is not recognized by the Spectrum core.
Is one of you know if the .SNA format can be converted to another format compatible for the Spectrum core of the Mister ?
For information, here is the CD that I'm talking about.

Thank you in advance for your help/tips.

RetroGold.JPG

Hi, if you add them into a vhd image for ESXDOS then you can load snapshots easily by just using it.

akeley wrote: ↑Fri Jun 02, 2023 3:33 am

The core is able to run .sna files ("Load Snapshot *Z80, SNA" in OSD), I've just tried to load a few and they work ok. Did you try your snapshots in an emulator?

Yes the .sna files (which are on my CD) work with the emulator SpecEmu V3.2.

I do confirm as well that none of them work on the Mister by using OSD load SNA, just have the 1st screen than hang.

kathleen wrote: ↑Sat Jun 03, 2023 6:40 pm

akeley wrote: ↑Fri Jun 02, 2023 3:33 am

The core is able to run .sna files ("Load Snapshot *Z80, SNA" in OSD), I've just tried to load a few and they work ok. Did you try your snapshots in an emulator?

Yes the .sna files (which are on my CD) work with the emulator SpecEmu V3.2.

specemu SNA.JPG

I do confirm as well that none of them work on the Mister by using OSD load SNA, just have the 1st screen than hang.

It will require same exact model to load.

Sna is a terible format. Its from the early days of spectrum emulation and should never be used now.

FPGA64 wrote: ↑Sat Jun 03, 2023 7:04 pm

Sna is a terible format. Its from the early days of spectrum emulation and should never be used now.

Agree, my intention was not to use this format absolutely. It is just because it is what I found on my old CD bought long time ago and wanted to save it to play the games on my Mister.

BUT, one more time, I feel stupid, let me explain why.

I have an external SSD (on a switched USB hub) where I transferred all the C64 & Spectrum files from my CD to it
If I've the SSD switched on before I start the Spectrum core, than the SNA files don't work (hangs on the 1st screen)
But, if I start the Spectrum core with the SSD off, (I've a folder Spectrum + rom + games also on the internal SD card) then switch on my SSD and open the SNA games which are on the SSD, then they work as they should.....

I then realized that with the SSD on, I haven't the start screen where I can choose tape "loading", "128", "48" etc. start screen that I have if I start the core with the SSD off .

I have well the BOOT.ROM into the Spectrum folder of the SSD however, but I certainly did something wrong when I copied it
Will recheck this

Anyway, now I can confirm that my SNA files are running fine under the Spectrum core.

I learnt thanks to your answers that the SNA is not the format to use, that some converter programs exists (under DOS) and that I can be stupid sometimes

Thanks again to all of you for your help.