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Booting the RP2350 from UART

pfister.dev

21–22 of 22 posts

Re: Booting the RP2350 from UART

#21

Earlier quoted context omitted.

Are you implying the SWD signals would send the RAM contents every time? If I had to do that, I would first use a logic analyzer like Saleae to capture the SWD signals of a JLink performing the necessary operations to load the image into RAM. Then figure out, from the bytes that get send and received, whatever needs to be parameterized, and where to put the image data itself, perhaps by capturing different scenarios,…

This is completely unnecessary since SWD is both trivial as well as well documented

Well... I wouldn't call it "trivial". But it is documented.

Re: Booting the RP2350 from UART

#22
post #14

Earlier quoted context omitted.

We (Pimoroni) actually shipped this technique in PicoVision, used to load the “GPU” firmware (an RP2040 used to offload the HDMI signal generation) at runtime- https://github.com/pimoroni/picovision/blob/main/drivers/dv_...

What are the advantages of doing this instead booting it through UART? Speed perhaps?

In theory you wouldn’t even need to load firmware- you could just manipulate the relevant registers directly over SWD for the silliest IO expander.

In our case it was the only choice. I’d say we’d use UART now but the RP2350 can pretty much do it all in one chip.

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