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Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
@Gordon
I think I've managed to make room for an 0603 polyfuse now - it's tight though! \o/
The markings for power are a bit difficult... I've moved them around to make them nearer the actual pins, but there's not enough space to move the SWD pads down, so the labels do have to go below them :(
With the crystal, the problem I have is that the STM32F4 is on a low power process, and the oscillator can't drive a 'normal' watch crystal reliably (at least not well enough to run it at the 32kHz it's trimmed it). It's got to have nearer a 4pF load capacitance, and I don't know if they even make the through-hole watch crystals like that.
I actually ordered 6000 crystals, found out they wouldn't work, and had to try and send them back. As expected crystals that actually work are twice the price, making them by far the most expensive part on the board (apart from the STM32).
It's not hard to buy one though, and they're not very painful in small quantities - ABS06-107. The 107 is very important (as I found out!).
They shouldn't be that much more difficult to solder than the ones with wires.