GF82.00-P-2000T Data Transmission Function

GF82.00-P-2000T Data Transmission Function

Data transfer in MOST
The audio gateway control unit (N93/1) makes it possible to provide all the information on the CAN interior (CAN-B) to each respective component in the MOST. It acts as an interface (gateway). To this end signals arriving at the audio gateway control unit (N93/1) are converted such that they can be sent by the MOST to the CAN interior (CAN-B) and vice versa. It is the clock-pulse generator that transmits information segments (data frames) on the bus system. A frame consists of 2 subframes. The sequence of many data frames then contains the complete information for the operation of the MOST components.

Light pulses are converted into electrical signals and back again by means of the optical transmitter and receiver diodes, which are integrated into every MOST component.

The MOST components can then receive or transmit the electrical signals. Source data and control data are transmitted.

The source data are transmitted synchronously, for instance as they are available on an audio CD, as blocks in subframes. By contrast, the control data are transferred asynchronously. They are split up, distributed using several subframes and sent off.

The control data are provided with an address (Code), which indicates for which MOST components the data are intended. Information arriving at the component is recompiled as individual data packages in the component and can then be processed. A data frame can thus contain the most varied of information (source and control data of all the components in the MOST).

The transmitting and receiving units are switched off when they are not required, in order to lower the quiescent current consumption (sleep mode). They are immediately switched off after the radio control panel and navigation unit (A2/56) is switched off or after the transmitter key (A8/1) is removed.

With a new optical information transmission start, the MOST can be activated with the help of the "ON switch (On/Off) of the radio control panel and navigation unit (A2/56) or by turning the transmitter key (A8/1) into position "circuit 15R ON", provided the system was not shut off before the transmitter key (A8/1) was removed. It is activated by an electrical signal in the wake-up line, which is actuated by the audio gateway control unit (N93/1).

With integrated telephone and inserted transmitter key (A8/1) it is also possible to actuate a wake-up call if a call comes in.

Regardless of the fact for which component the information is intended during the start, the edited light signal arrives at the MOST at full intensity.