Multiface 3 issue and multiloaders

[LeoVK83]

Hi all

A couple of questions about the Multiface 3 that I have just recently started using with my Speccy +3...

1. Most 48k games seem to save to disk and reload fine, but if I take a snapshot of a 128k game (for example “The Untouchables”), upon reloading the screen scrambles into flashing garbled nonsense and crashes. Is this a known issue?

2. Has anyone got any guides to using the Multiface 3 to save entire multi-load tape games to disk, so that you don’t need to revert to using tape again every time a new level needs loading into memory? I’m guessing this requires some additional advanced jiggery-pokery (technical terminology there)?

Thanks!

[Alcoholics Anonymous]

Sometimes a snapshot save can be corrupted if taken at an inopportune time.

But for The Untouchables specifically, there seems to be dsk versions of the game available:
https://spectrumcomputing.co.uk/index.p ... 96&id=5520

Hacking a program to load data from disk or other things takes some skill and time. It was done in the early days of emulation (see LLT and SLT files) before tap and dsk were supported. I adapted several multiloaders to disk for my ts2068 using those LLT and SLT files and I think I remember one of them was the Untouchables.

[LeoVK83]

Sometimes a snapshot save can be corrupted if taken at an inopportune time.

Interesting! Do you know what kind of conditions could cause this? Seems completely random as to what works and what doesn’t but, invariably, it’s the larger games that seem to have more trouble saving. I managed to get Kwik Snax to save after about 10 attempts the other night. Trying to get Addams Family to work too (particularly as it takes 10+ mins to load) but to no avail...!

[Alcoholics Anonymous]

Bad snapshots happen when either (1) there is so little stack space available that an nmi interrupt is going to push enough stuff to overwrite some part of the program or (2) the stack pointer is being used as a memory pointer rather than a stack pointer at the time the button is pressed so that an nmi interrupt writes stuff into memory that shouldn't be overwritten.

I would expect certain program types to be hard to snapshot (nirvana, eg) but otherwise most things should snapshot ok, which seems to be different from your experience! The mf3 can't be detected by software so programs can't foil it with protections. The safest place to snapshot is probably a game's menu.

[LeoVK83]

To be honest, I am wondering now whether the issue may have been down to me using some badly aged, cheap disks. I just bought a few Amsoft disks that have clearly been well cared for and stored properly (in their original card slip cases and spotless) and snapshots have been saving absolutely fine to them, without a glitch!

Perhaps files stored by the M3 are *particularly* sensitive to a bit of a worn disk?