Do you have a compiler for .uf2?

[Mr-Amnat]

Please help share .uf2 pi pico vga.
I can't compile it.
Thank you.

[markadev]

Yes! You can download the compiled .uf2 files from: https://github.com/markadev/AppleII-VGA/releases

Just choose the one for your Apple II model (II+ or IIe)

[jakubpolomsky]

Do you happen to have builds for apple II europlus? I am trying to get it running and I tried both iie and iiplus files, yet all I can see are the inverted @ signs and a blinking cursor in four lines (cycling through the four cursor positions when I advance on the lines on the composite connected monitor)

[jakubpolomsky]

Oh nevermind... I realized I was using the 74LS instead of LV... now everything works perfectly fine

[markadev]

Cool, glad to hear you got it working!

[Ret-Marut]

Hi, I have the same problem (inverted @ only, and after some hours I see flickering some LowRes artifacts). I have LVC buffers installed, though, could the be fake ones? I ordered them from china...
Regards
Bernd

[markadev]

Hi, I have the same problem (inverted @ only, and after some hours I see flickering some LowRes artifacts). I have LVC buffers installed, though, could the be fake ones? I ordered them from china... Regards Bernd

Hey there. It's always possible they could be fake but you can also double-check the 3.3v supply on the ICs and if you have a scope then you can check pin 31 on the Pico to see that the Apple 1MHz bus clock signal is making it through.

[Ret-Marut]

Hi Mark,
sorry, it took a while (because of other projects ;-), and here are my findings:

• The 1MHz clock on the Pico side looks weird. See the scope picture (bottom is the Apple 1 MHz clock, 2V/div, top is at pin 4 of LVC245, 1V/div, both taken with 10:1 prescaler, triggering on bottom signal, neg). There seems to be a jitter on the 3V side.
• lifting pin 4 (i.e. disconnecting the Pico I/O) showed a marginal change of the signal
• blocking with additional caps on the supply didn't help
• testing the 74LVC245's on a breadboard revealed nothing strange
• verifying the board wiring and connections also didn't show anything strange (I'm using the v1.6)
  I now ordered a set of new 74LVC245 from DigiKey, that's my last try then...

Regards
Bernd