Firmware for controllers of thermal sensors

Make regular scan of 8 sensors' pairs. USART speed 115200. Code for ../../kicad/stm32

Serial interface commands (ends with '\n'), small letter for only local processing:

0...7 send message to Nth controller, not broadcast (after number should be CAN command)
@ set/reset debug mode
a get raw ADC values
B send dummy CAN messages to broadcast address
b get/set CAN bus baudrate
c show coefficients for all thermosensors
D send dummy CAN messages to master (0) address
d get current CAN address of device
Ee end temperature scan
Ff turn sensors off
g group (sniffer) CAN mode (print to USB terminal all incoming CAN messages with alien IDs)
Hh switch I2C to high speed (100kHz)
Ii (re)init sensors
Jj get MCU temperature
Kk get values of U and I
Ll switch I2C to low speed (default, 10kHz)
Mm change master id to 0 (m) / broadcast (M)
N get build number
Oo turn onboard diagnostic LEDs On or off (both commands are local!)
P ping everyone over CAN
Qq get system time
Rr reinit I2C
s send CAN message (format: ID data[0..8], dec, 0x - hex, 0b - binary)
Tt start single temperature measurement
u unique ID (default) CAN mode
Vv very low speed
Xx go into temperature scan mode
Yy get sensors state over CAN (data format: 3 - state, 4,5 - presense mask [0,1], 6 - npresent, 7 - ntempmeasured
z check CAN status for errors

The command M allows to temporaly change master ID of all controllers to broadcast ID. So all data they sent will be accessed @ any controller.

I2C: PB6 (SCL) & PB7 (SDA)
USART1: PA9 (Tx) & PA10 (Rx)
CAN bus: PB8 (Rx), PB9 (Tx)
USB bus: PA11 (DM), PA12 (DP)
I2C multiplexer: PB0..PB2 (0..2 address bits), PB12 (~EN)
sensors' power: PB3 (in, overcurrent), PA8 (out, enable power)
signal LEDs: PB10 (LED0), PB11 (LED1)
ADC inputs: PA0 (V12/4.93), PA1 (V5/2), PA3 (I12 - 1V/A), PA6 (V3.3/2)
controller CAN address: PA13..PA15 (0..2 bits), PB15 (3rd bit); 0 - master, other address - slave

Variable data length: from 1 to 8 bytes. First (number zero) byte of every sequence is command mark (0xA5) or data mark (0x5A).

CMD_PING (0) request for PONG cmd
CMD_START_MEASUREMENT (1) start single temperature measurement
CMD_SENSORS_STATE (2) get sensors state
CMD_START_SCAN (3) run scan mode
CMD_STOP_SCAN (4) stop scan mode
CMD_SENSORS_OFF (5) turn off power of sensors
CMD_LOWEST_SPEED (6) lowest I2C speed
CMD_LOW_SPEED (7) low I2C speed (10kHz)
CMD_HIGH_SPEED (8) high I2C speed (100kHz)
CMD_REINIT_I2C (9) reinit I2C with current speed
CMD_CHANGE_MASTER_B (10) change master id to broadcast
CMD_CHANGE_MASTER (11) change master id to 0
CMD_GETMCUTEMP (12) MCU temperature value
CMD_GETUIVAL (13) request to get values of V12, V5, I12 and V3.3
CMD_GETUIVAL0 (14) answer with values of V12 and V5
CMD_GETUIVAL1 (15) answer with values of I12 and V3.3
CMD_REINIT_SENSORS (16) (re)init all sensors (discover all and get calibrated data)
CMD_GETBUILDNO (17) get by CAN firmware build number (uint32_t, littleendian, starting from byte #4)
CMD_SYSTIME (18) get system time in ms (uint32_t, littleendian, starting from byte #4)

byte 3 - Sensor number (10*N + M, where N is multiplexer number, M - number of sensor in pair, i.e. 0,1,10,11,20,21...70,71)
byte 4 - thermal data H
byte 5 - thermal data L

All temperature is in degrC/100!

byte 2 - type of data (CMD_GETUIVAL0 - V12 and V5, CMD_GETUIVAL1 - I12 and V3.3)

case CMD_GETUIVAL0

case CMD_GETUIVAL1

Voltage is in V/100, Current is in mA