On 05/06/12 16:53, Trent W. Buck wrote:
James Harper wrote:
Ideally this switch would have a dead mans reset too
This is typically called a watchdog. Linux has drivers for several chipsets.
Those hardware watchdog chipsets just reset everything, rather than specifically switch off some relays, though.. I thought? I admit I haven't used them beyond that function, so maybe they can do more.
A watchdog is just a chip. In most cases it's wired to the system reset but you could wire it to anything I guess, which is what I'd want. A system reset watchdog might work if there was a guarantee that the USB controlled device would reset everything to off, and I would have to have my controller software write to the watchdog device instead of using a watchdog daemon. The mythical 'black box' that I just connect to via USB would be better though. James