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- Three AFEs
- Temperatures measured via thermistors (AFEs)
- gpio's control the mux (for AFEs)
- adc: for reading measurements
- we talk to the AFEs and Current Sense using iso-spi
- LTC6811 is the chip (AFE/Battery Monitor) (6811-1)
- According to the datasheet, the 6811 is pin and software compatible with the 6804 used in MSXII. The changes seem to entirely affect electrical characteristics.
- So we should be able to reuse the majority of AFE driver code
Killswitch:
- The killswitch MCU has an Enable Line (PB9) and Monitor Line (PB5)
- The Enable Line is an output from the MCU that causes the relays to close if the killswitches are closed
- The Monitor Line is an input to the MCU that measures the state of the killswitches
Enable will activate the high side driver which sends a 12 V signal to the kill switches. If both are closed, the signal returns to the BMS carrier and powers the main relay coils (if the low side switches are also closed). When a kill switch is pressed, it opens and the relay coils do not receive 12 V, so they open and the car turns off. The regulations require that the car enters a BPS fault when a kill switch is pressed, and so we need a way of measuring if the signal has come back to the BMS carrier from the kill switches. In the lower-left corner of schematic page 5, you can see a voltage divider that sends a ~3.3 V monitor signal to the controller board if the kill switches are closed, 0 V if the kill switches are open.
Changes that probably need to be made to MS12 plutus to work with MS14 bms carrier board (if that firmware is reused, not comprehensive)
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