Wake-Up, Function

Normal wake-up (all)
Since the transmit and receive diodes and the D2B chip are automatically shut off if they are not required (sleep mode), a wake-up pulse is required at the beginning of a new data transmission in order to activate the system.
This is provided by the separate wake-up cable. The master unit issues a wake-up signal (electrical signal) which allows the voltage in the wake-up cable to drop to a defined level. The D2B chip in the components detects from the duration of the signal that this is a wake-up signal and the D2B ring "starts up". The D2B ring is therefore now switched on.
A wake-up can also take place in a "sleeping" system without the wake-up pulse from the master unit using the telephone system adapter when a telephone call is received, for example.

Diagnosis wake-up
(except model 215, 220 with MB radio audio 30/code 750a)
The master unit can be told to trigger a wake-up diagnosis signal using the diagnosis tool (model-specific, hand-held tester or start diagnosis) in order to run a diagnosis of the wake-up circuit. This signal differs from the wake-up signal by being considerably longer. The components react to this long wake-up pulse with a signal on the wake-up cable (message to master unit).
This means that the master unit can detect which components have received the long wake-up pulse. The diagnosis wake-up can only be triggered if the optical ring cannot "start up" because of a fault.
If all components have reported to the master unit, their power supply is in perfect working order.