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authorDavid A. Mellis <d.mellis@arduino.cc>2009-06-01 08:32:11 +0000
committerDavid A. Mellis <d.mellis@arduino.cc>2009-06-01 08:32:11 +0000
commitdb605dd18b11ecfb5cd9f92c721c52cb70543384 (patch)
tree8a9029ffc560970ce1204ba86785ad44ef044906 /libraries/Servo/Servo.cpp
First integration of the Arduino code in Processing 5503: PreProcessor and Compiler have been integrated with changes to the Sketch.
Compilation still has problems (Thread error on success, and can't handle non-pde files in a sketch). Modified the Mac OS X make.sh to copy the hardware, avr tools, and example over. Removing some of the antlr stuff. Disabling the Commander (command-line execution) for now. Added Library, LibraryManager, and Target. Added support for prefixed preferences (e.g. for boards and programmers).
Diffstat (limited to 'libraries/Servo/Servo.cpp')
-rwxr-xr-xlibraries/Servo/Servo.cpp133
1 files changed, 133 insertions, 0 deletions
diff --git a/libraries/Servo/Servo.cpp b/libraries/Servo/Servo.cpp
new file mode 100755
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--- /dev/null
+++ b/libraries/Servo/Servo.cpp
@@ -0,0 +1,133 @@
+#include <avr/interrupt.h>
+#include <wiring.h>
+#include <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
+*/
+
+
+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_ATmega8__)
+ TIMSK &= ~(_BV(TICIE1) | _BV(OCIE1A) | _BV(OCIE1B) | _BV(TOIE1) );
+#else
+ TIMSK1 &= ~(_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) {}
+
+uint8_t Servo::attach(int pinArg)
+{
+ return attach(pinArg, 544, 2400);
+}
+
+uint8_t Servo::attach(int pinArg, int min, int max)
+{
+ if (pinArg != 9 && pinArg != 10) return 0;
+
+ min16 = min / 16;
+ max16 = max / 16;
+
+ 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;
+}