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The LLC / ATmega2560 acts as a SPI slave to the MLC / Raspberry Pi. The data exchange repeats at 50 Hz. The communication is synchronous, i.e. the LLC waits for the MLC to initiate the exchange.

SPI is full duplex, the input and output data are exchanged simultaneously.

https://git.rwth-aachen.de/CPM/Project/Lab/software/blob/master/vehicle_atmega2560_firmware/vehicle_atmega2560_firmware/spi_packets.h

https://git.rwth-aachen.de/CPM/Project/Lab/software/blob/master/vehicle_atmega2560_firmware/vehicle_atmega2560_firmware/spi.cSee Mid Level Controller.

Inputs / Sensors

ADC

The ADC measures the battery voltage and the motor current. These are only used for monitoring, not control.

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