Adding Servo library (ServoTimer1 from the playground) by Jim Studt.

3 files changed, 198 insertions, 0 deletions

diff --git a/libraries/Servo/Servo.cpp b/libraries/Servo/Servo.cpp
new file mode 100755
index 0000000..c88e73a
--- /dev/null
+++ b/libraries/Servo/Servo.cpp
@@ -0,0 +1,125 @@
+#include <Servo.h>
+#include <avr/interrupt.h>
+
+/*
+  Servo.h - Hardware Servo Timer Library
+  Author: Jim Studt, jim@federated.com
+  Copyright (c) 2007 David A. Mellis.  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
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+
+uint8_t Servo::attached9 = 0;
+uint8_t Servo::attached10 = 0;
+
+void Servo::seizeTimer1()
+{
+  uint8_t oldSREG = SREG;
+
+  cli();
+  TCCR1A = _BV(WGM11); /* Fast PWM, ICR1 is top */
+  TCCR1B = _BV(WGM13) | _BV(WGM12) /* Fast PWM, ICR1 is top */
+  | _BV(CS11) /* div 8 clock prescaler */
+  ;
+  OCR1A = 3000;
+  OCR1B = 3000;
+  ICR1 = clockCyclesPerMicrosecond()*(20000L/8);  // 20000 uS is a bit fast for the refresh, 20ms, but 
+                                                  // it keeps us from overflowing ICR1 at 20MHz clocks
+                                                  // That "/8" at the end is the prescaler.
+#if defined(__AVR_ATmega168__)
+  TIMSK1 &=  ~(_BV(OCIE1A) | _BV(OCIE1B) | _BV(TOIE1) );
+#else
+  TIMSK &= ~(_BV(TICIE1) | _BV(OCIE1A) | _BV(OCIE1B) | _BV(TOIE1) );
+#endif
+
+  SREG = oldSREG;  // undo cli()    
+}
+
+void Servo::releaseTimer1() {}
+
+#define NO_ANGLE (0xff)
+
+Servo::Servo() : pin(0), angle(NO_ANGLE), min16(34), max16(150) {}
+Servo::Servo(int min, int max) : pin(0), angle(NO_ANGLE), min16(min / 16), max16(max / 16) {}
+
+uint8_t Servo::attach(int pinArg)
+{
+  if (pinArg != 9 && pinArg != 10) return 0;
+
+  pin = pinArg;
+  angle = NO_ANGLE;
+  digitalWrite(pin, LOW);
+  pinMode(pin, OUTPUT);
+
+  if (!attached9 && !attached10) seizeTimer1();
+
+  if (pin == 9) {
+    attached9 = 1;
+    TCCR1A = TCCR1A & ~_BV(COM1A0) | _BV(COM1A1);
+  }
+  
+  if (pin == 10) {
+    attached10 = 1;
+    TCCR1A = TCCR1A & ~_BV(COM1B0) | _BV(COM1B1);
+  }
+  return 1;
+}
+
+void Servo::detach()
+{
+  // muck with timer flags
+  if (pin == 9) {
+    attached9 = 0;
+    TCCR1A = TCCR1A & ~_BV(COM1A0) & ~_BV(COM1A1);
+    pinMode(pin, INPUT);
+  } 
+  
+  if (pin == 10) {
+    attached10 = 0;
+    TCCR1A = TCCR1A & ~_BV(COM1B0) & ~_BV(COM1B1);
+    pinMode(pin, INPUT);
+  }
+
+  if (!attached9 && !attached10) releaseTimer1();
+}
+
+void Servo::write(int angleArg)
+{
+  uint16_t p;
+
+  if (angleArg < 0) angleArg = 0;
+  if (angleArg > 180) angleArg = 180;
+  angle = angleArg;
+
+  // bleh, have to use longs to prevent overflow, could be tricky if always a 16MHz clock, but not true
+  // That 8L on the end is the TCNT1 prescaler, it will need to change if the clock's prescaler changes,
+  // but then there will likely be an overflow problem, so it will have to be handled by a human.
+  p = (min16*16L*clockCyclesPerMicrosecond() + (max16-min16)*(16L*clockCyclesPerMicrosecond())*angle/180L)/8L;
+  if (pin == 9) OCR1A = p;
+  if (pin == 10) OCR1B = p;
+}
+
+uint8_t Servo::read()
+{
+  return angle;
+}
+
+uint8_t Servo::attached()
+{
+  if (pin == 9 && attached9) return 1;
+  if (pin == 10 && attached10) return 1;
+  return 0;
+}
diff --git a/libraries/Servo/Servo.h b/libraries/Servo/Servo.h
new file mode 100755
index 0000000..780367d
--- /dev/null
+++ b/libraries/Servo/Servo.h
@@ -0,0 +1,51 @@
+#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.
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#include <inttypes.h>
+#include <wiring.h>
+
+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();
+    Servo(int, int); // pulse length for 0 degrees in microseconds, 540uS default
+                     // pulse length for 180 degrees in microseconds, 2400uS default
+    uint8_t attach(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();
+};
+
+#endif
diff --git a/libraries/Servo/keywords.txt b/libraries/Servo/keywords.txt
new file mode 100755
index 0000000..918c46a
--- /dev/null
+++ b/libraries/Servo/keywords.txt
@@ -0,0 +1,22 @@
+#######################################
+# Syntax Coloring Map Servo
+#######################################
+
+#######################################
+# Datatypes (KEYWORD1)
+#######################################
+
+Servo  KEYWORD1
+
+#######################################
+# Methods and Functions (KEYWORD2)
+#######################################
+attach KEYWORD2
+detach KEYWORD2
+write KEYWORD2
+read KEYWORD2
+attached KEYWORD2
+
+#######################################
+# Constants (LITERAL1)
+#######################################