(I work at Oxide, though I wasn't around for the initial chip selection process)
It's at least partially a matter of timing: Oxide was picking its initial hardware in roughly 2020, and the RP2040 wasn't released until 2021.
A handful of people have done ports, e.g. https://github.com/oxidecomputer/hubris/pull/2210, but I expect to stick with STM32s for the foreseeable future – we've got a lot to do, and they're working well enough!
The internal RFD on the SP's design still talks about choosing RISC-V, and I don't think (or am simply bad at using search) that the move ended up being in an RFD.
RP2040 and RP2350 PIO makes producing VGA signals criminally easy.
But many other µCs can do it too, at least to some degree. Even Atmels.
I just realized that my keyboard has two of those RP2040's on it, which is giving me some very bad ideas.
my thoughts too. this is a hello world bare metal step up. doing it to get to grips w gpio on a full blown os is cool too though
There's probably a well documented backstory on why Oxide choose stm32xx nucleo. I'm guessing VGA signals were not a top priority for hubris
(I work at Oxide, though I wasn't around for the initial chip selection process)
It's at least partially a matter of timing: Oxide was picking its initial hardware in roughly 2020, and the RP2040 wasn't released until 2021.
A handful of people have done ports, e.g. https://github.com/oxidecomputer/hubris/pull/2210, but I expect to stick with STM32s for the foreseeable future – we've got a lot to do, and they're working well enough!
The rack has no screens, so no need to drive VGA, it's true.
Probably the best history on the choice of going with ARM comes from here: https://news.ycombinator.com/item?id=28989138
The internal RFD on the SP's design still talks about choosing RISC-V, and I don't think (or am simply bad at using search) that the move ended up being in an RFD.