How do the kill switches work?

[Arwen]

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For the first, I've updated the Wiki to indicate it's stored in the keyboard's flash memory.

Just to be clear: @pfeerick says it's in EEPROM storage, and I suspect he's right.  (The relevant difference is whether or not the kill switches are preserved when the flash memory is rewritten during a firmware update.)

One note, Jack's keyboard firmware can send a special key sequence on disable and enable of the kill switches. This is to allow future OS level detection of change, like re-enabling WiFi chip. It's still early days, so we will have to see if Jack's firmware becomes the "new" default firmware. Already we have seen a change in the default OS from Debian to Manjaro.

I can't imagine that it wouldn't be; it's keyboard controller firmware.  It either does its job or it doesn't.  The only distinguishing factor here is closed-source vs open-source, and I find it difficult to believe that the kind of people who are interested in Pinebooks wouldn't embrace the latter.

The difference on what device the kill switch status is stored on the keyboard is not really clear. We do not have the schematics of the keyboard to determine if it has just 1 re-writable flash memory. Or 2. So I went with the more generic wording. But, I did clarify that it's stored on the keyboard. Even works before the OS is booted. (Jack or examination of what Jack has done, may clarify it. But, I don't have the skill to determine it.)

As for open source keyboard firmware, if you look at Pine64, they encourage others to do the work. Pine64 supplies the hardware, the hard part, (no pun intended). Thus, it's much easier for others to do the software, like OS distro and firmware for U-Boot on SPI.

One note, the trackpad is connected to the keyboard. So their is 1 USB interface for both.