C100501-001 REV.1.0
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Atarian Computing
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C100501-001 REV.1.0
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KLund1
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Re: C100501-001 REV.1.0
I have this board, and I think the Shifter and DMA labels are switched.
FYI
FYI
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exxos
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Re: C100501-001 REV.1.0
Yes it looks wrong.KLund1 wrote: 30 Aug 2021 18:44 I have this board, and I think the Shifter and DMA labels are switched.
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stephen_usher
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Re: C100501-001 REV.1.0
Yeah, why would the Shifter be next to the WD1772? Makes no sense.
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.
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PaulJ
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Re: C100501-001 REV.1.0
Take your ohm meter out and measure from pin 11 of the 1771 to pin 30 on the shifter and dma chip. When you get ~0 ohms that's the dma chip. The other device will have a significantly higher resistance reading.
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olivier.jan
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Re: C100501-001 REV.1.0
I have the same motherboard in my Mega 2 and I keep wondering why U32 and U35 are not populated. Why bother having the sockets if these chips are not installed and why are these chips required on all other STs but not this one?
Retro stuff
520 STF/ 1040 STE / Mega ST / 2 Mega STE / 2 H5
2 x 600XL with U1MB /SOFIA 2/ AVG CART / and a few 1050
Apple //c, Commodore 128, Mac Classic, SE/30, LC, IIvi and PB G3 (Clamshell)
Amiga 600 and a few 486 and 386.
Many Nintendo G&W and other electronic games from the late 70s/early 80s.
520 STF/ 1040 STE / Mega ST / 2 Mega STE / 2 H5
2 x 600XL with U1MB /SOFIA 2/ AVG CART / and a few 1050
Apple //c, Commodore 128, Mac Classic, SE/30, LC, IIvi and PB G3 (Clamshell)
Amiga 600 and a few 486 and 386.
Many Nintendo G&W and other electronic games from the late 70s/early 80s.
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exxos
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Re: C100501-001 REV.1.0
From factory ?! Assume someone removed them at some point ? Looks to be the 244 buffers ?olivier.jan wrote: 12 May 2022 06:21 I have the same motherboard in my Mega 2 and I keep wondering why U32 and U35 are not populated. Why bother having the sockets if these chips are not installed and why are these chips required on all other STs but not this one?
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olivier.jan
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Re: C100501-001 REV.1.0
The machine still had the seal when I got it and the picture posted here shows the same sockets without the chips, so I suspect it's from Factory.
Moreover, the Mega ST 2 without this chips is still working perfectly :shock:
Moreover, the Mega ST 2 without this chips is still working perfectly :shock:
Retro stuff
520 STF/ 1040 STE / Mega ST / 2 Mega STE / 2 H5
2 x 600XL with U1MB /SOFIA 2/ AVG CART / and a few 1050
Apple //c, Commodore 128, Mac Classic, SE/30, LC, IIvi and PB G3 (Clamshell)
Amiga 600 and a few 486 and 386.
Many Nintendo G&W and other electronic games from the late 70s/early 80s.
520 STF/ 1040 STE / Mega ST / 2 Mega STE / 2 H5
2 x 600XL with U1MB /SOFIA 2/ AVG CART / and a few 1050
Apple //c, Commodore 128, Mac Classic, SE/30, LC, IIvi and PB G3 (Clamshell)
Amiga 600 and a few 486 and 386.
Many Nintendo G&W and other electronic games from the late 70s/early 80s.
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exxos
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Re: C100501-001 REV.1.0
:WTF:olivier.jan wrote: 12 May 2022 10:27 The machine still had the seal when I got it and the picture posted here shows the same sockets without the chips, so I suspect it's from Factory.
Moreover, the Mega ST 2 without this chips is still working perfectly :shock:
Can you post images top and bottom of that board ?
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olivier.jan
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Re: C100501-001 REV.1.0
Ok, I should stay away from my beer pump for a while…. I opened the machine and the chips are there which makes much more sense. Sorry for the confusion. :headbang:
Retro stuff
520 STF/ 1040 STE / Mega ST / 2 Mega STE / 2 H5
2 x 600XL with U1MB /SOFIA 2/ AVG CART / and a few 1050
Apple //c, Commodore 128, Mac Classic, SE/30, LC, IIvi and PB G3 (Clamshell)
Amiga 600 and a few 486 and 386.
Many Nintendo G&W and other electronic games from the late 70s/early 80s.
520 STF/ 1040 STE / Mega ST / 2 Mega STE / 2 H5
2 x 600XL with U1MB /SOFIA 2/ AVG CART / and a few 1050
Apple //c, Commodore 128, Mac Classic, SE/30, LC, IIvi and PB G3 (Clamshell)
Amiga 600 and a few 486 and 386.
Many Nintendo G&W and other electronic games from the late 70s/early 80s.
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