Diff: Adafruit_PWMServoDriver.cpp

Revision:

0:ed0c8a6481fd

Child:

1:ac6c5e17c3d3

diff -r 000000000000 -r ed0c8a6481fd Adafruit_PWMServoDriver.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Adafruit_PWMServoDriver.cpp	Sat Aug 17 06:59:05 2013 +0000
@@ -0,0 +1,87 @@
+/*************************************************** 
+  This is a library for our Adafruit 16-channel PWM & Servo driver
+
+  Pick one up today in the adafruit shop!
+  ------> http://www.adafruit.com/products/815
+
+  These displays use I2C to communicate, 2 pins are required to  
+  interface. For Arduino UNOs, thats SCL -> Analog 5, SDA -> Analog 4
+
+  Adafruit invests time and resources providing this open source code, 
+  please support Adafruit and open-source hardware by purchasing 
+  products from Adafruit!
+
+  Written by Limor Fried/Ladyada for Adafruit Industries.  
+  BSD license, all text above must be included in any redistribution
+  
+  Ported to mbed by Brian Dickman, mbed.org user bxd.
+ ****************************************************/
+
+#include <Adafruit_PWMServoDriver.h>
+
+Adafruit_PWMServoDriver::Adafruit_PWMServoDriver(I2C *i2c, uint8_t addr) {
+  _i2c = i2c;
+ 
+  // Arduino WIRE library takes address as 7-bit (unshifted), mbed takes 8 bit.
+  _i2caddr = addr << 1;
+}
+
+void Adafruit_PWMServoDriver::begin(void) {
+ reset();
+}
+
+
+void Adafruit_PWMServoDriver::reset(void) {
+ write8(PCA9685_MODE1, 0x0);
+}
+
+void Adafruit_PWMServoDriver::setPWMFreq(float freq) {
+  //Serial.print("Attempting to set freq ");
+  //Serial.println(freq);
+  
+  float prescaleval = 25000000;
+  prescaleval /= 4096;
+  prescaleval /= freq;
+  prescaleval -= 1;
+  //printf("Estimated pre-scale: %f\r\n", prescaleval);
+  uint8_t prescale = floor(prescaleval + 0.5);
+  //printf("Final pre-scale: %f", prescale);  
+  
+  uint8_t oldmode = read8(PCA9685_MODE1);
+  uint8_t newmode = (oldmode&0x7F) | 0x10; // sleep
+  write8(PCA9685_MODE1, newmode); // go to sleep
+  write8(PCA9685_PRESCALE, prescale); // set the prescaler
+  write8(PCA9685_MODE1, oldmode);
+  wait_ms(5);
+  write8(PCA9685_MODE1, oldmode | 0xa1);  //  This sets the MODE1 register to turn on auto increment.
+                                          // This is why the beginTransmission below was not working.
+  //  Serial.print("Mode now 0x"); Serial.println(read8(PCA9685_MODE1), HEX);
+}
+
+void Adafruit_PWMServoDriver::setPWM(uint8_t num, uint16_t on, uint16_t off) {
+  //Serial.print("Setting PWM "); Serial.print(num); Serial.print(": "); Serial.print(on); Serial.print("->"); Serial.println(off);
+
+  uint8_t data[] = { LED0_ON_L+4*num, on, on >> 8, off, off >> 8 };
+  _i2c->write(_i2caddr, (const char *)data, 5);
+  /*
+  WIRE.beginTransmission(_i2caddr);
+  WIRE.write(LED0_ON_L+4*num);
+  WIRE.write(on);
+  WIRE.write(on>>8);
+  WIRE.write(off);
+  WIRE.write(off>>8);
+  WIRE.endTransmission();
+  */
+}
+
+uint8_t Adafruit_PWMServoDriver::read8(uint8_t addr) {
+    char data;
+    _i2c->write(_i2caddr, &data, 1, true);
+    _i2c->read(_i2caddr, &data, 1);
+    return (uint8_t)data;
+}
+
+void Adafruit_PWMServoDriver::write8(uint8_t addr, uint8_t d) {
+    char data[] = { addr, d };
+    _i2c->write(_i2caddr, data, 2);
+}
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