Onboard switch?

PicoCalc
1

Photos of the main board show a dual pcb switch SW701 with no apparent lable or reference in the assembly manual… What is this for ?

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Seems to be some kind of boot selection/debug option.

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Yeah, not sure. It seems to be physically located near the PSRAM, but that probably doesn’t matter.

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Just a guess: one puts mcu into programming mode, and the other one (100% guess) selects which microprocessor’s serial goes to the USB-C port

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I lied. The first switch toggles boot mode of the stm32 as well as connect its serial to the serial<->USB chip. The second switch is to switch the actual USB-C port connection between the serial<->USB chip and the stm32 (has its own USB interface).

So depending on which way you need to program the stm32, one or both switches must be flipped.

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This would make a great addition to the wiki: PicoCalc/wiki at master · clockworkpi/PicoCalc · GitHub

If you have the time to setup a PR that’d be great, otherwise I’ll try and remember once I get ramped up. (not affiliated, just enjoying)