HALT when launching game in SSE 3.9.0

[Flam]

Hi
Steem 3.9.0
Windows XP
TOS 1.02
Some of my games does not work anymore with 3.9.0 (all ok with 3.8.2)
Two of them in attachment
Description of actual outcome : message HALT at the beginning

[Steven Seagal]

Interesting.
Strangely, it halts with 512K and 1MB, but not above.
The settings aren't right, TOS and ST model are incompatible:

STE0; T102-7; 1024K; #; C1; C2; WM 1-1,0-1,0

T102 is for STF.
Normally Steem warns you at cold reset.
Despite this, it still worked in v3.8.2 and before but in v3.9.0 I changed memory detection emulation.
Normally it is more accurate.
Is it? Hard to tell. But it's not a bug, you should select STF or TOS 1.62, as no STE was delivered with TOS 1.02.

Thx for the report.

[czietz]

I don't know the accuracy of MMU emulation in Steem, however, on the real hardware the MMU is different between STF and STE. Hence, TOS 1.02 memory detection algorithm will indeed only work with an STF MMU, not with an STE one. TOS 1.06 and 1.62 will only work with an STE MMU, TOS 2.06 checks the machine type (STF vs. STE) and uses the proper algorithm accordingly. I wrote something about it for EmuTOS: https://sourceforge.net/p/emutos/code/c ... detect.txt

Conclusion: Steem is correct to crash during memory initialization with TOS 1.02 on an emulated STE.

[Flam]

Everything is fine now with STF
Thanks a lot Steven

[ijor]

Can you run a 192K TOS image on the STE, without a hardware mod, at all? Too lazy to check the STE schematics and see what would happen with the GLUE Reset vectors remap ...

Honestly, it was a nice hack to be able to run old TOS on Steem STE mode. Oh, well, guess emulation is becoming too accurate.

[Steven Seagal]

So it's not a bug, it's a feature.
Yes, I used that document to change Steem, with a difference between STF and STE MMU.
The emulated STE will still take a STF TOS with memory sizes 2MB, 4MB. Because tests are negative with a full bank anyway.