Connecting to the bootloader UART directly

It's probably best to look up ST's own bootloader - the impression I got was that it looks on all serial ports, so you may be able to hook up to USART2 and use that instead.

That's a nice clue. Will look into that.

Well, I thought, after my probs with the serial ports on my Mac, that going platform independent could also be accomplished by putting the files on a SD card and having one of the espruinos flashing the other. At least now that we have that streaming file io.