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The pads next to the resonator can take a 32kHz crystal - I was considering pre-installing them, but they're surprisingly expensive when that size (way more than the resonator) and I'm not sure it'll be that useful
Wow, yeah, crystal prices go way up when you want them tiny like that. If people are going to be soldering them on at home, wouldn't we likely be using a radial can type, like we do now on the Espruino1v3, not the miniscule SMD ones? It looks like there's plenty of room to bend it over the resonator. In that case, why not leave holes for a radial can type, instead of SMD pads?
DrAzzy
@DrAzzy the FET is the same FET that's used for battery switching (I think it's connected to B0 right now, but that might change). The idea is if you're plugged into USB then you can use that same FET to get a powered output. It only pulls up to VUSB, but it's still pretty handy.
The pads next to the resonator can take a 32kHz crystal - I was considering pre-installing them, but they're surprisingly expensive when that size (way more than the resonator) and I'm not sure it'll be that useful - The F4 can do RC calibration against the high speed oscillator, so for most things it'll be more than accurate enough. And yes, 84Mhz. I got the impression that you can overclock it to 168Mhz (like other F4 parts) but that's not really a priority right now :)
@FyberChris the 411 looks interesting - I hadn't considered it before. To be honest the 401 is still pretty good for power usage when in sleep mode. The only UFPQFN48 right now seems to be the STM32F411CE though, and that's basically 2x the price :(