Servo.h File Reference

Interrupt driven Servo library using 16 bit timers - Version 2. More...

#include "api/Common.h"
#include <inttypes.h>
#include "stm32/ServoTimers.h"

Classes
struct	ServoPin_t
	Pin of a servo channel. More...
struct	servo_t
	Servo channel data. More...
class	Servo
	Servo motor controller. More...

Macros
#define	Servo_VERSION   2
	Software version of this library.
#define	MIN_PULSE_WIDTH   544
	Shortest pulse sent to a servo, in microseconds.
#define	MAX_PULSE_WIDTH   2400
	Longest pulse sent to a servo, in microseconds.
#define	DEFAULT_PULSE_WIDTH   1500
	Default pulse width when a servo is attached, in microseconds.
#define	REFRESH_INTERVAL   20000
	Minimum time to refresh servos, in microseconds.
#define	SERVOS_PER_TIMER   12
	Maximum number of servos controlled by one timer.
#define	MAX_SERVOS   (_Nbr_16timers * SERVOS_PER_TIMER)
	Maximum number of servos supported by the available 16 bit timers.
#define	INVALID_SERVO   255
	Flag indicating an invalid servo index.

Detailed Description

Interrupt driven Servo library using 16 bit timers - Version 2.

A servo is activated by creating an instance of the Servo class passing the desired pin to the attach() method. The servos are pulsed in the background using the value most recently written using the write() method.

Note

analogWrite of PWM on pins associated with the timer are disabled when the first servo is attached. Timers are seized as needed in groups of 12 servos - 24 servos use two timers, 48 servos will use four. The sequence used to seize timers is defined in timers.h

The methods are:

• Servo: class for manipulating servo motors connected to Arduino pins.
• attach(pin): attach a servo motor to an i/o pin.
• attach(pin, min, max): attach to a pin setting min and max values in microseconds, default min is 544, max is 2400.
• write(): set the servo angle in degrees (an invalid angle that is valid as pulse in microseconds is treated as microseconds).
• writeMicroseconds(): set the servo pulse width in microseconds.
• read(): get the last written servo pulse width as an angle between 0 and 180.
• readMicroseconds(): get the last written servo pulse width in microseconds (was read_us() in first release).
• attached(): return true if there is a servo attached.
• detach(): stop an attached servo from pulsing its i/o pin.