Hi have a couple of Mega STEs, 1 in bits 1 complete, The complete one sometime flickers when I open the hard disk I thought the hard disk might be failing as its the original so I have put a bluescsi in and it does the same with that. I tried a ultra-satan and again the same thing. It only does it every know any then is likely to be a DMA issue maybe a PSU? (I have a third scrap mobo so I might have another DMA if its not damaged I might try it).
Thanks
Brian
Mega STE
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UnderTheRain
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Re: Mega STE
I've read your extensive article on DMA so I would be looking at a PSU, CPY or DMA I'll check my scrap board on the weekend and see what the state of the CPU and DMA are and maybe try swapping them over failing that I'll go through the PSU. You put in a lot of work on DMA's thank you Mr Exxos.
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Steve
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Re: Mega STE
Can you be a bit more descriptive, when you say 'it sometimes flickers when I open the hard disk' ... What sometimes flickers?
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rubber_jonnie
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Re: Mega STE
I'm with Steve, what flickers? The screen is all I can think of, but if software is working, but the screen is flickering, I can't imagine it being something like DMA or CPU.Steve wrote: 21 Mar 2025 07:18 Can you be a bit more descriptive, when you say 'it sometimes flickers when I open the hard disk' ... What sometimes flickers?
Power seems more likely to be the cause to me. Or caps.
A video of the symptom would help.
Usual steps apply, power, clocks etc & remove any socketed ICs clean the pins, tweak the PLCC sockets, spray with contact cleaner and reassemble.
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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Badwolf
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Re: Mega STE
Is the Ultrasatan externally powered (ie. not drawing power from the MSTE)?
BW
BW
DFB1 Open source 50MHz 030 and TT-RAM accelerator for the Falcon
Smalliermouse ST-optimised USB mouse adapter based on SmallyMouse2
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Smalliermouse ST-optimised USB mouse adapter based on SmallyMouse2
FrontBench The Frontier: Elite 2 intro as a benchmark
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