Does anyone happen to know how to keep the serial console from going to sleep after a bit of inactivity? At some point I see a message that the UART clock's been gated, and then only the Kindle side can wake it up again.
It's obviously some power management thing. Has anyone seen a setting for that someplace?
Even better would be another IO line like DTR or RTS that would wake it up.
Also, is there any GPIO-like unused pin anyplace that the system has access to?