Make universal blink example work with W boards

[will-v-pi]

This detects between W and non-W boards using the ADC, as described in "Connecting to the Internet with Raspberry Pi Pico W-series"

This method should work for all boards powered from VSYS, which should cover all standard use cases for the blink example

This does increase the UF2 file size from 96KB to 1,023KB, as the combined UF2 contains 2 copies of the wifi firmware, but in flash it is still only half that size

[lurch]

I guess the universal.h is only designed to run on the official Raspberry Pi microcontroller boards (Pico, Pico W, Pico WH, Pico 2, Pico 2 W) rather than on any 3rd-party RP2040 or RP2350 boards, so perhaps it ought to be named something like pico_universal.h ?

[will-v-pi]

I guess the universal.h is only designed to run on the official Raspberry Pi microcontroller boards (Pico, Pico W, Pico WH, Pico 2, Pico 2 W) rather than on any 3rd-party RP2040 or RP2350 boards, so perhaps it ought to be named something like pico_universal.h ?

It does run on quite a few 3rd-party boards - as long as they use the same LED and VSYS pins it will work (which applies to most of the boards on my desk)

[lurch]

It does run on quite a few 3rd-party boards - as long as they use the same LED and VSYS pins it will work (which applies to most of the boards on my desk)

Oh, neat!

[peterharperuk]

Could we add an example partition json for this? And maybe a readme for how to run the universal examples on a blank Pico 2 board?

peterh@rpi5-peterh-dev2:~ $ picotool load blink_universal.uf2
WARNING: Multiple family IDs in a single UF2 file - only using first one
Family ID 'rp2040' cannot be downloaded anywhere
ERROR: This file cannot be loaded onto a device with no partition table

[will-v-pi]

Could we add an example partition json for this? And maybe a readme for how to run the universal examples on a blank Pico 2 board?

peterh@rpi5-peterh-dev2:~ $ picotool load blink_universal.uf2
WARNING: Multiple family IDs in a single UF2 file - only using first one
Family ID 'rp2040' cannot be downloaded anywhere
ERROR: This file cannot be loaded onto a device with no partition table

This doesn't use partitions - the error you're getting is because when picotool sees two UF2s concatenated (which is what a universal UF2 is), it only uses the first file, which is the RP2040 one. That could be fixed, but this is an existing issue for all universal UF2s.

These universal UF2s are designed for drag & drop instead

[peterharperuk]

These universal UF2s are designed for drag & drop instead

Ok, understood. It does work if you drag and drop. Maybe we should say this in the readme.

[peterharperuk]

It works. I seem to be getting an interesting copy error from windows (I don't remember getting this before?) with pico1 devices , presumably because the device has rebooted before the whole uf2 has been written? It still works despite this although it's a bit disconcerting.

[will-v-pi]

It works. I seem to be getting an interesting copy error from windows (I don't remember getting this before?) with pico1 devices , presumably because the device has rebooted before the whole uf2 has been written? It still works despite this although it's a bit disconcerting.

Yes, I get that too - I think it doesn't occur for the smaller universal binaries because the device doesn't disappear until after Windows thinks it's loaded the whole file, but this one is larger so you get this error when the device disappears

[will-v-pi]

@peterharperuk I think I've fixed it with that latest commit - it now puts the last RP2040 UF2 block at the end of the file, so the RP2040 doesn't reboot until it has the whole file

The fix is gated to only run when compiling on Unix-like OSes, as it requires tail and truncate which may not be available on others. At some point this functionality could be added into picotool, but that can happen later.