Well, that's another issue.... already tried that only getting some (not many) garbage on screen... already tested cable with another Atari and all goodstephen_usher wrote: 11 Mar 2025 07:51 Sounds like you need to put a terminal on the serial port and use the diag cartridge. It’s failing before it can properly display anything on the screen.
However, having a red screen is a positive sign as that means that it’s reading the ROM and starting the diagnostics.
Atari Mega ST 1 Rev 1 no boot
-
Dwh18
- Posts: 26
- Joined: 21 Feb 2025 08:38
Re: Atari Mega ST 1 Rev 1 no boot
-
stephen_usher
- Site sponsor
- Posts: 7376
- Joined: 13 Nov 2017 19:19
- Location: Oxford, UK.
Re: Atari Mega ST 1 Rev 1 no boot
This suggests that the system can't talk to the MFP (68901) correctly or the MFP clock isn't working. Check pins 17 and 18 for oscillation from the crystal circuit. It should be 2.4576MHz.
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.
-
rubber_jonnie
- Site Admin
- Posts: 14888
- Joined: 17 Aug 2017 19:40
- Location: Essex
Re: Atari Mega ST 1 Rev 1 no boot
RAM errors tend to show as a white border and black screen, I think you have something entirely different going on.Dwh18 wrote: 11 Mar 2025 10:11COmpletely black screenrubber_jonnie wrote: 11 Mar 2025 08:30
So is it a completely black screen or a black screen in low reswith a white border?
@stephen_usher is right about the the red screen.
I'd try looking at what @stephen_usher has suggested.
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...
-
Dwh18
- Posts: 26
- Joined: 21 Feb 2025 08:38
Re: Atari Mega ST 1 Rev 1 no boot
Well, almost quitting and leaving this Motherboard and searching for a new one... anyone in EU that repairs Ataris?
-
PhilC
- Moderator
- Posts: 7441
- Joined: 23 Mar 2018 20:22
Re: Atari Mega ST 1 Rev 1 no boot
If you do decide to give up with that motherboard, then please send it to me, id like to have a look at it and would post the results on the forum.Dwh18 wrote: 26 Mar 2025 20:48 Well, almost quitting and leaving this Motherboard and searching for a new one... anyone in EU that repairs Ataris?
If it ain't broke, test it to Destruction.
Who is online
Users browsing this forum: apple [bot], ClaudeBot, harveymush, petal [bot] and 1 guest