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V2RetroComputing / analog

∀2 Analog VGA card for the Apple II computer line
MIT License
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Kapton Tape Masked Pico W pin #18

Open baz4096 opened 1 year ago

baz4096 commented 1 year ago

I've just noticed in one of the Tindie images, the Pico W RUN pin is masked with kapton tape, but the non-Wireless version isn't. I can't find any mention of masking any pins off, is this something I should be doing?

Masked pin:

https://cdn.tindiemedia.com/images/resize/zkVL8SAwADsTMNlKTqUq5UxlFvg=/p/full-fit-in/2400x1600/i/97799/products/2023-01-11T21%3A10%3A14.900Z-v2-analog-w.jpg?1673443949 https://cdn.tindiemedia.com/images/resize/zbUoMKf0rmjaOy2Pp3JLhiinn0Y=/p/full-fit-in/2400x1600/i/97799/products/2023-01-12T05%3A28%3A54.678Z-v2-analog-byop.jpg?1673472556

No masked pin:

https://cdn.tindiemedia.com/images/resize/YXppaIqB0wOAd4m_HjGg-x8-TWA=/p/full-fit-in/2400x1600/i/97799/products/2023-01-12T05%3A28%3A54.678Z-v2-analog-lc.jpg?1673472556

Thanks!

Verault commented 1 year ago

Great Question Baz4096. I too was going to ask about this same thing.

dkgrizzly commented 1 year ago

The original GERBERS for the board had the RESET line connected, which turned out to cause the RP2040 to boot too slow and reboot every time the Apple was reset. Isolating that pin allows the RP2040 to boot fast enough to catch the first writes to screen memory which is used to detect the machine type.

Verault commented 1 year ago

Just to clarify, the kapton tape is no longer needed on later revisions?

baz4096 commented 1 year ago

As far as I can read from the commits, the Rev1 gerber was modified and committed Apr 17th as part of the repo reorganisation; the filename changed from "AppleII-Pico-F_Cu.gtl" to "V2-Analog-Rev1-F_Cu.gtl"

analog/GERBERS-Rev1/AppleII-Pico-F_Cu.gtl includes the reset track. (Available until 17th April) analog-hardware/GERBERS-Rev1/V2-Analog-Rev1-F_Cu.gtl has the reset track removed. (From 17th April onwards)

The version of board I have includes the extra track. I've already soldered the Pico in place, so if I need to, I'll cut the trace where it emerges between Pico pins 12 & 13.

I'm still unsure if I need to isolate the reset pin, I guess I'll find out soon. My level shifters have arrived.

Verault commented 1 year ago

Thanks Baz4096. Please keep us informed on what you find.

dkgrizzly commented 1 year ago

Yes, if the trace is present, cut it. Otherwise you'll have issues with the autodetection and the RP2040 will reboot any time you hit ctrl-reset.