Audi AADC2017 Hardware Description page 32

Starting the Car
7. Set The Mode Switch back to RC Mode.
8. Now you can turn on the controller again.
9. Normally, you need to calibrate the speed controller to the output of the radio controller. This
setup routine maps the maximum motor speed to the maximum PWM signal of the radio
controller system and the minimum motor speed to the minimum PWM signal of the radio
controller system. The PWM signals from the Arduino which are used in software driven mode
are different from the signals from the radio system, so normally the speed controller has to be
calibrated each time the mode is switched from Arduino to the Radio System and vice versa.
You can use a little trick can be used to avoid this effort.
When the speed controller is powered on (after pressing the Button Motor in the side sills), it
waits for the zero position (PWM signal which corresponds to motor speed zero set during
calibration procedure). During this time, the red LED of the speed controller is on. When the
speed controller gets the zero position it does some more beeping and the green LED is also
turned on and the speed controller works properly.
You can adjust this zero position by the potentiometer THROTTLE TRIM. Therefore, after
turning the power for the speed controller on (some first beeping from it) you can adjust this
potentiometer to set the correct zero position. If you found the correct position the speed
controller does some more beeping. Maybe you have to try this multiple times, each time
switch the motor on and try another position of the potentiometer.
31.05.2017 v1.7 Audi Autonomous Driving Cup 2017 - Hardware Description
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