Hello @TRowe ,
As you mentioned, the library allows to spin the motor in both direction. It is just a question of the sign of the target speed (which is done by the MC Pilot).
The PWM input command is managed by a state machine in esc.c file and is a bit different.
The target speed in ESC_POSITIVE_RUN is computed as follow :
new_speed = ((pHandle->Ton_value-pESC_params->Ton_min) * (pESC_params->speed_max_valueRPM - pESC_params->speed_min_valueRPM) / pESC_params->delta_Ton_max) + pESC_params->speed_min_valueRPM;
with Ton_value computed from PWM input.
It will be indeed always positive.
The esc state machine is designed to avoid any injury with a drone propeller for instance. It is why we implemented the ESC_ARMING state to guarantee that the motor can not start full speed directly out of reset, even if the flight controller send the max duty cycle.
I do not know what your target application is, but if you want to get rid of the security aspects of the state machine, it is quite easy to set a PWM Ton_0Speed_value targeting 0 speed, and sending a negative speed for all values between 0 and Ton_0Speed_value and positive value for all values between Ton_0Speed_value and Ton_max. But be very careful, without anything else, your motor will run Max speed in reverse direction if there is no PWM signal...(which will be probably the case after a power up)
Hope it helps.
Regards
Cedric
