Received HIGHWAY.MTX as part of my MFX hardware. Unfortunately this .MTX file doesn’t start. It only shows a black screen with ‘LOADING…PLEASE WAIT’ and that’s it. Apparently it tries to load a second part which is either not present or can’t load..
Is there a way to run this game on my MFX MTX?
Highway encounter
Re: Highway encounter
Some multipart .mtx games do not load properly with "user mtx.." , I believe there's a dot COM version of this game, you can load the game that way instead on your MFX, or use the audio tape version.
Re: Highway encounter
I'm dredging up 40 odd year old memories here, I could be wrong but...
Highway encounter and some of the later MTX512 only conversions (F1 simulator, Soul of a Robot, Attack of the killer Tomatoes maybe) were actually written to run from #0100. Basically they were COM files but loaded from tape.
The loader program loaded in a chunk of code as a headerless data block, performed some memory remapping to CPM mode and moved chunk 1 into place. It then reversed the mapping back to basic mode and then repeated the process with chunk2 (and maybe chunk 3, 4 etc).
Once all the chunks were loaded and in place, the last step, instead of returning to basic mode, stayed in CPM mode and did a jump to 0100, just as if it was a COM file loaded off disc.
USER MTX falls over with this sort of loader, it's designed to load single part MTX files that load in one, with no second stage loader. What happens is that as soon as the second stage code takes over, it's calling the ROM to load the headerless block. With no way to patch the rom everything grinds to a stop at that point, the code is awaiting tape input that never happens.
Highway encounter and some of the later MTX512 only conversions (F1 simulator, Soul of a Robot, Attack of the killer Tomatoes maybe) were actually written to run from #0100. Basically they were COM files but loaded from tape.
The loader program loaded in a chunk of code as a headerless data block, performed some memory remapping to CPM mode and moved chunk 1 into place. It then reversed the mapping back to basic mode and then repeated the process with chunk2 (and maybe chunk 3, 4 etc).
Once all the chunks were loaded and in place, the last step, instead of returning to basic mode, stayed in CPM mode and did a jump to 0100, just as if it was a COM file loaded off disc.
USER MTX falls over with this sort of loader, it's designed to load single part MTX files that load in one, with no second stage loader. What happens is that as soon as the second stage code takes over, it's calling the ROM to load the headerless block. With no way to patch the rom everything grinds to a stop at that point, the code is awaiting tape input that never happens.
Re: Highway encounter
Give this a go ...
- Attachments
-
- HIGHWAY.zip
- remove the ,ffd from the filename before copying to the MFX
- (18.5 KiB) Downloaded 125 times
Re: Highway encounter
Thank you very much! Transferred to A: and used cpmvdp highway.com to run
Works fine…
(It was not on my distributed SD card)….. Just the HIGHWAY.MTX
Works fine…
(It was not on my distributed SD card)….. Just the HIGHWAY.MTX
Re: Highway encounter
It was not on your SD card because Martin just created it
Re: Highway encounter
The 40 year old memories about Highway Encounter were pretty good it turned out. Re-building the COM file wasn't super difficult.
The other 3 games I mentioned actually have a different loader system. F1SIM has already been done. I think the other 2 might be doable as well, but they're not looking as straighforward as this one was.
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stephen_usher
- Posts: 366
- Joined: 27 Nov 2016 19:58
Re: Highway encounter
How plausable would it be to make a RAM dump system, maybe using NMI, similar to those on the Spectrum and same to a file on either the CFX or MFX?
The problematic games could then be fixed to run from "disk".
I'm guessing the hardest part if the memory paging and loading it back in.
The problematic games could then be fixed to run from "disk".
I'm guessing the hardest part if the memory paging and loading it back in.
Re: Highway encounter
probably doable to make those snapshots but not worth the effort IMHO.. some games clash with high ram code above address #C000-D#700 SDX/CFX/MFX routines .. so the .run file will need extra header for code-relocation and possibly VDP setup too .. I have converted a few extra games to .run that way, including for example: Quantum / Downstream-danger / C5 etc .. works fine on my clone SDX and my CFX too.
Re: Highway encounter
Is that not covered by one of the F9 options in Andey Key's Memu ?stephen_usher wrote: ↑24 Oct 2025 19:50 How plausable would it be to make a RAM dump system, maybe using NMI
I've never used it, but i can see save snapshot under F9-s on the instructions on his website