Rainbow Electronics CAN интерфейс - Manual (Page 11)

BOSCH
ROBERT BOSCH GmbH, Postfach 50, D-7000 Stuttgart 1
Sep. 1991
Part A - page 9
Acknowledgment
All receivers check the consistency of the message being received and will
acknowledge a consistent message and flag an inconsistent message.
Sleep Mode / Wake-up
To reduce the system’s power consumption, a CAN-device may be set into sleep mode
without any internal activity and with disconnected bus drivers. The sleep mode is
finished with a wake-up by any bus activity or by internal conditions of the system. On
wake-up, the internal activity is restarted, although the transfer layer will be waiting for
the system’s oscillator to stabilize and it will then wait until it has synchronized itself to
the bus activity (by checking for eleven consecutive ’recessive’ bits), before the bus
drivers are set to "on-bus" again.
In order to wake up other nodes of the system, which are in sleep-mode, a special
wake-up message with the dedicated, lowest possible IDENTIFIER (rrr rrrd rrrr; r =
’recessive’ d = ’dominant’) may be used.
Basic Concepts