Thanks BWBadwolf wrote: Tue Jan 30, 2024 1:41 pmThere are four chips.HigashiJun wrote: Mon Jan 29, 2024 9:44 am Oh, and BTW, may we know which TOS version you're trying to run ?
If you want TOS 2.06, then you also need a TOS decoder to make it work.
Two have TOS1.04UK/EmuTOSUK 192k in them. One has EmuTOSPL and Tos1.04UK in it.
These three chips have been tested in my STFM.
The last chip has TOS2.06 and EmuTOS256 in it. I've suggested to Arti changing the chip in case he's randomly picked the TOS2.06 version by accident (none are labelled, I figured it'd be obvious). I've also suggested trying the chips in his STFM, which is known to work. Not heard back.
BW
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MegaST ROM adapter - black screen
- rubber_jonnie
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Re: MegaST ROM adapter - black screen
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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Re: MegaST ROM adapter - black screen
Thank you @Badwolf.
- HigashiJun
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Re: MegaST ROM adapter - black screen
Is the yellow capacitor soldered on one side only ?
- HigashiJun
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Re: MegaST ROM adapter - black screen
@Badwolf
When did you burn the EPROM for @arti040 ?
When did you burn the EPROM for @arti040 ?
Re: MegaST ROM adapter - black screen
Yup. As in the documentation.
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Re: MegaST ROM adapter - black screen
It's only a decoupling cap but that's the point of it being there if it's only connected on one side?
It shouldn't make any real difference but it should be soldered each end.
It shouldn't make any real difference but it should be soldered each end.
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
Re: MegaST ROM adapter - black screen
Ouch, I misunderstood the question. Of course, it is soldered from both sides! 
- rubber_jonnie
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Re: MegaST ROM adapter - black screen
OK, so looking at the bottom I can see two solder joints that don't look right, shown by the arrows:
The top one looks like it has bridged across to ground, and the bottom looks like it is a cold or incomplete joint.
I'd still suggest that you need to change the jumper header to a square pin type as those round pins won't make good contact through that jumper, they are too small.
The top one looks like it has bridged across to ground, and the bottom looks like it is a cold or incomplete joint.
I'd still suggest that you need to change the jumper header to a square pin type as those round pins won't make good contact through that jumper, they are too small.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
Re: MegaST ROM adapter - black screen
Start of January. It's not EPROM bitrot. I'm still using uncovered EPROMS from two years ago.
What I would suggest is putting the EPROM in the dualtos-equipped STFM I know Arti has to check the ROM is working and is the right one!
BW
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Smalliermouse ST-optimised USB mouse adapter based on SmallyMouse2
FrontBench The Frontier: Elite 2 intro as a benchmark
Smalliermouse ST-optimised USB mouse adapter based on SmallyMouse2
FrontBench The Frontier: Elite 2 intro as a benchmark