Enable speed/temperature multiplexing on same wire #14
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Allows for longer connecting wires
When Speed Sensor is Multiplexed with NTC 10k thermistor like on motors with Z910 connector, we need to ignore low ADC values when the hall crosses the magnet and speed sensor digital pin is pulled down by hall sensor. With 220k pull-up resistor a good starting point is to set SP_TEMP_MULTIPLEX to 150. For this setup to work, connect the SS1 pin on controller to MOTOR_TEMP pin. If real NTC 10k resistance is close to 150, your motor is on fire
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Enables speed and temperature multiplexing on the same (usually white) wire. Works with 10k NTC thermistor with customizable Beta value. To retrofit into existing motor with speed sensor, connect NTC between black (negative) and white (speed sensor) wire in the motor. On controller side, bridge SS (speed sensor) to MOTOR_TEMPERATURE pins and one lead of 220ohm resistor. Connect the other end of resistor to 3.3v source on the board (1117 voltage regulator or analog reference pin).
Set R_TEMP_PULLUP to combined resistance of built-in pullup and 220ohm resistor - you could measure the resistance between 3.3v point and white wire when it is not connected to motor.
Set NTC_BETA to Beta value of NTC 10k thermistor in the motor.
Set SP_TEMP_MULTIPLEX to ADC threshold for pull-down (speed sensor hall) signal. Good starting point is 200.