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authorDavid A. Mellis <d.mellis@arduino.cc>2009-08-15 14:48:42 +0000
committerDavid A. Mellis <d.mellis@arduino.cc>2009-08-15 14:48:42 +0000
commit50f77c7210a490d8fee28348fcda811ca0bdf615 (patch)
treec5ed76441bcdd7c51b6bf07d7b0ba16444dbaee6 /libraries/Servo/Servo.h
parent159051b8f814edb7474912ad6d04058d34f2d173 (diff)
parent79b7ecdd92973f4aa67a6bcaa8bd12a10e5b5133 (diff)
Moving the processing-5503 branch (used for Arduino 0017) into the trunk.
Diffstat (limited to 'libraries/Servo/Servo.h')
-rwxr-xr-xlibraries/Servo/Servo.h98
1 files changed, 69 insertions, 29 deletions
diff --git a/libraries/Servo/Servo.h b/libraries/Servo/Servo.h
index 0b0e8db..9a25c65 100755
--- a/libraries/Servo/Servo.h
+++ b/libraries/Servo/Servo.h
@@ -1,10 +1,6 @@
-#ifndef Servo_h
-#define Servo_h
-
/*
- Servo.h - Hardware Servo Timer Library
- Author: Jim Studt, jim@federated.com
- Copyright (c) 2007 David A. Mellis. All right reserved.
+ Servo.h - Interrupt driven Servo library for Arduino using 16 bit timers- Version 2
+ Copyright (c) 2009 Michael Margolis. All right reserved.
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
@@ -21,32 +17,76 @@
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
+/*
+
+ 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 that analogWrite of PWM on pins associated with the timer are disabled when the first servo is attached.
+ Timers are siezed as needed in groups of 12 servos - 24 servos use two timers, 48 servos will use four.
+
+ The methods are:
+
+ Servo - Class for manipulating servo motors connected to Arduino pins.
+
+ attach(pin ) - Attaches a servo motor to an i/o pin.
+ attach(pin, min, max ) - Attaches to a pin setting min and max values in microseconds
+ default min is 544, max is 2400
+
+ write() - Sets the servo angle in degrees. (invalid angle that is valid as pulse in microseconds is treated as microseconds)
+ writeMicroseconds() - Sets the servo pulse width in microseconds
+ read() - Gets the last written servo pulse width as an angle between 0 and 180.
+ readMicroseconds() - Gets the last written servo pulse width in microseconds. (was read_us() in first release)
+ attached() - Returns true if there is a servo attached.
+ detach() - Stops an attached servos from pulsing its i/o pin.
+ */
+
+#ifndef Servo_h
+#define Servo_h
+
#include <inttypes.h>
+#define Servo_VERSION 2 // software version of this library
+
+#define MIN_PULSE_WIDTH 544 // the shortest pulse sent to a servo
+#define MAX_PULSE_WIDTH 2400 // the longest pulse sent to a servo
+#define DEFAULT_PULSE_WIDTH 1500 // default pulse width when servo is attached
+#define REFRESH_INTERVAL 20000 // minumim time to refresh servos in microseconds
+
+#if defined(__AVR_ATmega1280__)
+#define MAX_SERVOS 48 // the maximum number of servos (valid range is from 1 to 48)
+#else
+#define MAX_SERVOS 12 // this library supports up to 12 on a standard Arduino
+#endif
+
+#define INVALID_SERVO 255 // flag indicating an invalid servo index
+
+typedef struct {
+ uint8_t nbr :6 ; // a pin number from 0 to 63
+ uint8_t isActive :1 ; // true if this channel is enabled, pin not pulsed if false
+} ServoPin_t ;
+
+typedef struct {
+ ServoPin_t Pin;
+ unsigned int ticks;
+} servo_t;
+
class Servo
{
- private:
- uint8_t pin;
- uint8_t angle; // in degrees
- uint8_t min16; // minimum pulse, 16uS units (default is 34)
- uint8_t max16; // maximum pulse, 16uS units, 0-4ms range (default is 150)
- static void seizeTimer1();
- static void releaseTimer1();
- static uint8_t attached9;
- static uint8_t attached10;
- public:
- Servo();
- uint8_t attach(int);
- // pulse length for 0 degrees in microseconds, 544uS default
- // pulse length for 180 degrees in microseconds, 2400uS default
- uint8_t attach(int, int, int);
- // attach to a pin, sets pinMode, returns 0 on failure, won't
- // position the servo until a subsequent write() happens
- // Only works for 9 and 10.
- void detach();
- void write(int); // specify the angle in degrees, 0 to 180
- uint8_t read();
- uint8_t attached();
+public:
+ Servo();
+ uint8_t attach(int pin); // attach the given pin to the next free channel, sets pinMode, returns channel number or 0 if failure
+ uint8_t attach(int pin, int min, int max); // as above but also sets min and max values for writes.
+ void detach();
+ void write(int value); // if value is < 200 its treated as an angle, otherwise as pulse width in microseconds
+ void writeMicroseconds(int value); // Write pulse width in microseconds
+ int read(); // returns current pulse width as an angle between 0 and 180 degrees
+ int readMicroseconds(); // returns current pulse width in microseconds for this servo (was read_us() in first release)
+ bool attached(); // return true if this servo is attached, otherwise false
+private:
+ uint8_t servoIndex; // index into the channel data for this servo
+ int8_t min; // minimum is this value times 4 added to MIN_PULSE_WIDTH
+ int8_t max; // maximum is this value times 4 added to MAX_PULSE_WIDTH
};
-#endif
+#endif \ No newline at end of file