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Enabling servo usage on boards with PWM current control

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Enabling servo usage on boards with PWM current control
timer5 is used by some boards like the Mini Rambo for controlling motor current via PWM, see stepper.cpp.
```cpp
  #ifdef MOTOR_CURRENT_PWM_XY_PIN
    pinMode(MOTOR_CURRENT_PWM_XY_PIN, OUTPUT);
    pinMode(MOTOR_CURRENT_PWM_Z_PIN, OUTPUT);
    pinMode(MOTOR_CURRENT_PWM_E_PIN, OUTPUT);
    digipot_current(0, motor_current_setting[0]);
    digipot_current(1, motor_current_setting[1]);
    digipot_current(2, motor_current_setting[2]);
    //Set timer5 to 31khz so the PWM of the motor power is as constant as possible. (removes a buzzing noise)
    TCCR5B = (TCCR5B & ~(_BV(CS50) | _BV(CS51) | _BV(CS52))) | _BV(CS50);
  #endif
}
```
Using the same timer for controlling servos results in loss of motor control. So use timer4/3 for those boards instead.
[See discussion here.](http://shop.prusa3d.com/forum/software-f13/enabling-auto-leveling-in-firmware-t416-s40.html)
This commit is contained in:
PheiPheiPhei 2016-03-21 03:03:55 +01:00 committed by PheiPheiPhei
parent 10caee2b7c
commit adb5375a09
1 changed files with 8 additions and 3 deletions
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11
Marlin/servo.h
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@ -60,12 +60,17 @@
// Say which 16 bit timers can be used and in what order
#if defined(__AVR_ATmega1280__) || defined(__AVR_ATmega2560__)
#define _useTimer5
//#define _useTimer1
#define _useTimer3
#define _useTimer4
//typedef enum { _timer5, _timer1, _timer3, _timer4, _Nbr_16timers } timer16_Sequence_t ;
typedef enum { _timer5, _timer3, _timer4, _Nbr_16timers } timer16_Sequence_t ;
#ifndef MOTOR_CURRENT_PWM_XY_PIN
//Timer 5 is used for motor current PWM and can't be used for servos.
#define _useTimer5
//typedef enum { _timer5, _timer1, _timer3, _timer4, _Nbr_16timers } timer16_Sequence_t ;
typedef enum { _timer5, _timer3, _timer4, _Nbr_16timers } timer16_Sequence_t ;
#else
typedef enum {_timer3, _timer4, _Nbr_16timers } timer16_Sequence_t ;
#endif
#elif defined(__AVR_ATmega32U4__)
//#define _useTimer1