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700 points elipsitz | 1 comments | | HN request time: 0.214s | source
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ryukoposting ◴[] No.41195070[source]
I can't imagine someone using an RP2040 in a real product, but the RP2350 fixes enough of my complaints that I'd be really excited to give it a shot.

There's a lot going for the 2040, don't get me wrong. TBMAN is a really cool concept. It overclocks like crazy. PIO is truly innovative, and it's super valuable for boatloads of companies looking to replace their 8051s/whatever with a daughterboard-adapted ARM core.

But, for every cool thing about the RP2040, there was a bad thing. DSP-level clock speeds but no FPU, and no hardware integer division. A USB DFU function embedded in boot ROM is flatly undesirable in an MCU with no memory protection. PIO support is extremely limited in third-party SDKs like Zephyr, which puts a low ceiling on its usefulness in large-scale projects.

The RP2350 fixes nearly all of my complaints, and that's really exciting.

PIO is a really cool concept, but relying on it to implement garden-variety peripherals like CAN or SDMMC immediately puts RP2350 at a disadvantage. The flexibility is very cool, but if I need to get a product up and running, the last thing I want to do is fiddle around with a special-purpose assembly language. My hope is that they'll eventually provide a library of ready-made "soft peripherals" for common things like SD/MMC, MII, Bluetooth HCI, etc. That would make integration into Zephyr (and friends) easier, and it would massively expand the potential use cases for the chip.

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1. tliltocatl ◴[] No.41199401[source]
>>> extremely limited in third-party SDKs like Zephyr

So is almost any non-trivial peripheral feature. Autonomous peripheral operation, op-amps, comparators, capture/compare timers…

Zephyr tries to provide a common interface like desktop OSes do and this doesn't really work. On desktop having just the least common denominator is often enough. On embedded you choose your platform because you want the uncommon features.