What was the reason for that over 373 ? Timings - some ATARI's work, some don't - you know all about that :) 373s (latches) latch on falling edge, 374s (flipflops) latch on rising edge, so there's a [minimum of] a half clock cycle difference if using the same firmware. All the work's been done on 3...

exxos wrote: ↑Wed Apr 10, 2024 8:05 pm Cool, my falcon ones won't fit then, I will order one off amazon or somewhere then. Shame rapid don't seem to sell them.

Falcon is also 2.54, but the expansion headers are 30 and 50 pin, IIRC. Pi4 is 40 pin.

Same as a (full size) IDE connector.

BW

ROM SIMMS? You're a madman!

I love it. Great work.

BW

Thanks all.

So my takeaway is that whilst 5V will let you boot to the desktop, whether you can *see* it depends on quite a few things.

So I think I'll stop recommending it as a troubleshooting shortcut without that nota bene.

Cheers,

BW.

@Badwolf I could prepare two versions with and without latches to see how everything behaves. But in the end I would like to have compatibility with faster machines too. Simpler version could be an option for people with standard machines (who know they will never, ever buy any accelerator ;-)). .....

For people who still use SCART 12V is also needed to generate the correct signals for TVs to recognize the picture. Is that just for the RGB/Composite switching? I think I've used SCART for colour with just 5V. BUT, MONO for the ST2VGA would still nee 12V as it powers the RGB/MONO IC. Aha. There's ...

Really quick one. I didn't want to pollute another thread. I've seen it said a lot -- and I just saw RJ (I think) mention it on another thread -- that the 12V line isn't needed for the ST to boot. I thought this was true too but couldn't get anything out of either of my STs when relying on this. Tur...

This is R/W timing: Tww - 100ns, Twds - 10ns Twdh - 20ns opl3Timing.png The only one there I think that matters is Tww of 100ns. If you drive it from a combination of ROM3 and A1 (if you want to identify chips with on A1, A2 etc.) then the minimum assertion time for an ST would be two clock cycles....

Hi! I found the Atari Falcon030 Service Guide, but it is electronic oriented, and there are not all the PCB layout informations, like : where is the fan connector? Where is the sound connector? What is this switch for, and this one, etc? Any chance I could find a good pic of the PCB with all the ma...

Sorry -- daughter's not been well today. Not really had time to read all this properly. Responding a bit ad-hoc. Need for this latch was purely to save state of adress lines to have certain pattern set on OPL3 data / address lines, after setting this I need to (assert /WR low or high OPL3 for certai...