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RAMBLINý MAN

by Tom Cantrell

Start ý Little Network ý Mini-Message ý LO BAT ý Caravan ý Sources and PDF

LO BAT

With the growing population of electronic hangers-on, a carýs quiescent power consumption becomes an issue. Indeed, my ý99 has a gadget that preventively disconnects the battery before the accessories drain it to the point when it canýt start the engine.

It's no surprise then that the only special message defined by LIN is SLEEP (IDENT field 0x80). The master, and only the master, issues the SLEEP command. In return, slaves can send a WAKEUP signal to the bus that is a single byte 0x80 (not an entire message). Upon detecting a WAKEUP signal, all nodes powerup and the master resumes normal messaging. Should the master not respond to a WAKEUP call (within 128 bit times), the WAKEUP is issued up to three times before something is presumed seriously amiss.

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