Remote Reboot Jig

Developing Linux on a remote board can be challenging, because sometimes you'll need to reboot a crashed board. This can be simplified using a remote reboot jig consisting of a USB relay board.

Here is a ASCII art diagram of the schematic:

--                       --- |     +| [ USB relay ]|+      | | 5V  |                      | board | |    -| -|-      |  --                        ---

Basically, you put the relay between the power source and the board on the Vbus line. You could do this by splicing a USB extension cord, by buying the appropriate power connector, or very fancy using a USB breakout board.

You can find a cheap USB relay on eBay, by searching for "USB relay smart home". Single channel suffices for 1 board, but you could go large, of course. Controlling the board (given you bought the HID "driverless" version) is done through this software:

jorik@neon:~$ cat bin/cycle.sh hidusb-relay-cmd on 2 hidusb-relay-cmd off 2
 * 1) !/bin/sh

Of course, on/off may need to be swapped, since the relay is SPDT.