For a primary school teaching project, my wife and I were given two
BBC micro:bit embedded systems.  They've been around since 2015, but
this is the first time I've used them.

One of my regular irritations in new designs is startup time.  Complex
firmware bootloaders slow things down.

So I used Atom and PlatformIO to code a blinky, and looked at the time
between 3.3V power and I/O pin rise.  It is 2.5ms, which is quite
nice.

http://dev.laptop.org/~quozl/20171107-bbc-microbit-startup.png

Looking into it, there are two microcontrollers; the Nordic nRF51822
runs the application, and an NXP KL26Z is used as the USB interface.

https://en.wikipedia.org/wiki/Micro_Bit

--=20
James Cameron
http://quozl.netrek.org/
--=20
http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist
.