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by roeles 1636 days ago
For those interested: I ported FreeRTOS 9 to an nRF52840 in my previous job. This family used a lot. It's in my Tado smart radiator knobs, in the AirTags.

I can only compare it to FreeScale chips, but one thing that pleasantly surprised me is the flexibility in pin-assignment. Instead of the pin-mux that we'd have to do on the MK24, I could just assign pins during usb/i2c init without any limitations. The SDK is quite elaborate, although sometimes a bit difficult to use in C++.

1 comments

An any-to-any IO multiplexer turns out to be pretty large in silicon area. You're paying extra for that feature as opposed to devices where each pin has a choice of just say 3 functions.

For most users, they prefer to have the chips cheaper and spend an extra few minutes of engineer time figuring out which pins need to be hooked up to what.

I can see for smaller volume devices where engineer time dominates, and devices that you want to be really field reconfigurable, the all-to-all mux is worth it though.

Thanks for the insight! I didn't choose the nRF, it was a given. I believe it was chosen due to being similar to the MK24 (also an M4) and having Bluetooth. The chips ended going into wearables, and BTLE was seen as the way to configure/upgrade the devices.