added an enable_active_high field (default true) to BLDCDriver6PWM

this is to use the enable pin on the DRV8316, which is actually a
driver_off pin, and therefore active-low for enabled state

Author: runger1101001

src/drivers/BLDCDriver6PWM.cpp

@@ -24,7 +24,7 @@ BLDCDriver6PWM::BLDCDriver6PWM(int phA_h,int phA_l,int phB_h,int phB_l,int phC_h
 // enable motor driver
 void  BLDCDriver6PWM::enable(){
     // enable_pin the driver - if enable_pin pin available
-    if ( _isset(enable_pin) ) digitalWrite(enable_pin, HIGH);
+    if ( _isset(enable_pin) ) digitalWrite(enable_pin, enable_active_high?HIGH:LOW);
     // set zero to PWM
     setPwm(0, 0, 0);
 }
@@ -35,7 +35,7 @@ void BLDCDriver6PWM::disable()
   // set zero to PWM
   setPwm(0, 0, 0);
   // disable the driver - if enable_pin pin available
-  if ( _isset(enable_pin) ) digitalWrite(enable_pin, LOW);
+  if ( _isset(enable_pin) ) digitalWrite(enable_pin, enable_active_high?LOW:HIGH);
 
 }
 
@@ -82,4 +82,4 @@ void BLDCDriver6PWM::setPwm(float Ua, float Ub, float Uc) {
 // Set voltage to the pwm pin
 void BLDCDriver6PWM::setPhaseState(int sa, int sb, int sc) {  
   // TODO implement disabling
-}
+}

src/drivers/BLDCDriver6PWM.h

@@ -37,6 +37,7 @@ class BLDCDriver6PWM: public BLDCDriver
   	int pwmB_h,pwmB_l; //!< phase B pwm pin number
   	int pwmC_h,pwmC_l; //!< phase C pwm pin number
     int enable_pin; //!< enable pin number
+    bool enable_active_high = true;
 
     float dead_zone; //!< a percentage of dead-time(zone) (both high and low side in low) for each pwm cycle [0,1]