For some unknown reason, this also happens to me with my FPGA shifter sometimes when there is no keyboard connected.

Yep - 10x. Presumably the load is in the ST side of things. Or some effect that I'm not aware of. I will try it with a smaller series resistor when I get a chance.

I got some of the aforementioned Schmitt trigger buffers, this is what the output clock looks like (with 33R in series).

If the main ASICs could be converted to FPGA models, then the possibility of running nearly the entire system (apart from the IO ports) at 3.3v is there.

Icky wrote: ↑

Tue Oct 30, 2018 7:13 pm

Or you could go all Apple on this and have your own proprietary connector and sell the adaptor cables at a premium.

I suppose that's one option!

Yes but I don't think anyone is really going to care, since I'm not a company.

...Right?

I'd like to take an informal poll, if anyone who has an opinion would care to respond - Which video connector would you prefer to see on this mod: HDMI or DVI? HDMI connectors are cheaper and use less board space (and need a smaller hole in the back of the ST). But the DVI connector seems a lot more...

I would definitely love to have a UK keyboard (my ST is German) but whether I can afford it or not is down to the postage to Australia for such a big object. I really only need the key caps. Any chance I could buy a whole board and you just post the key caps and throw the rest in the bin? I understa...

Problem is tri-state the buffers, when the FPGA goes tri-state, nothing is driving the buffers, so logic output to the bus will be "random"... The buffers need to be isolated, but there is no control for that. So I can't use "normal" buffers ICs.. only FET based ones which don't have tri-state issu...

Hi, sorry I haven't read the complete thread but I see you're looking for bidirectional 3.3 to 5v interface logic - the one I used for the data bus on the HDMI thing is 74ALVC164245DL,112. It has two groups of 8 pins with a direction control and tristate pin per group. They're about $2 each in x10 p...