Forward communication (ECU-Sensor):
The ECU supplies the sensors with voltage.
The commands of the ECU are created by changing the voltage from VHigh to VLow.
Each command starts at VHigh.
after that an rising slope (VLow to VHigh)symbolize a logical 0 and a falling slope ( VHigh to VLow) 0 a logical 1.
The command data package of the master is each 32 bit long and defined as follows:
| MSB | LSB | |||
| Physical address | Command | Extended data | Register data | CRC |
| Register Address | Sensor type dependent command (data sheet of the sensor manufacturer) | Extended sensor type dependent data area | Register data which are written to the sensor | Error detection |
| xxxx | xxxx | xxxx xxxx | xxxx xxxx | xxxx xxxx |
| 4 bit | 4 bit | 8 bit | 8 bit | 8bit |
|
32 bit length |
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Physical limits of the current and voltage levels take from the DSI specifiction.
