add optional Wire, clean up and modernize examples

Author: ladyada

Adafruit_PWMServoDriver.cpp

@@ -18,23 +18,36 @@
 #include <Adafruit_PWMServoDriver.h>
 #include <Wire.h>
 
-#if defined(ARDUINO_SAM_DUE)
- #define Wire Wire1
-#endif
-
-
 // Set to true to print some debug messages, or false to disable them.
 //#define ENABLE_DEBUG_OUTPUT
 
 
 /**************************************************************************/
 /*! 
-    @brief  Instantiates a new PCA9685 PWM driver chip with the I2C address
+    @brief  Instantiates a new PCA9685 PWM driver chip with the I2C address on the Wire interface. On Due we use Wire1 since its the interface on the 'default' I2C pins.
     @param  addr The 7-bit I2C address to locate this chip, default is 0x40
 */
 /**************************************************************************/
 Adafruit_PWMServoDriver::Adafruit_PWMServoDriver(uint8_t addr) {
   _i2caddr = addr;
+
+#if defined(ARDUINO_SAM_DUE)
+  _i2c = &Wire1;
+#else
+  _i2c = &Wire;
+#endif
+}
+
+/**************************************************************************/
+/*! 
+    @brief  Instantiates a new PCA9685 PWM driver chip with the I2C address on a TwoWire interface
+    @param  i2c  A pointer to a 'Wire' compatible object that we'll use to communicate with
+    @param  addr The 7-bit I2C address to locate this chip, default is 0x40
+*/
+/**************************************************************************/
+Adafruit_PWMServoDriver::Adafruit_PWMServoDriver(TwoWire *i2c, uint8_t addr) {
+  _i2c = i2c;
+  _i2caddr = addr;
 }
 
 /**************************************************************************/
@@ -43,7 +56,7 @@ Adafruit_PWMServoDriver::Adafruit_PWMServoDriver(uint8_t addr) {
 */
 /**************************************************************************/
 void Adafruit_PWMServoDriver::begin(void) {
-  Wire.begin();
+  _i2c->begin();
   reset();
 }
 
@@ -110,13 +123,13 @@ 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);
 #endif
 
-  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();
+  _i2c->beginTransmission(_i2caddr);
+  _i2c->write(LED0_ON_L+4*num);
+  _i2c->write(on);
+  _i2c->write(on>>8);
+  _i2c->write(off);
+  _i2c->write(off>>8);
+  _i2c->endTransmission();
 }
 
 /**************************************************************************/
@@ -130,7 +143,7 @@ void Adafruit_PWMServoDriver::setPWM(uint8_t num, uint16_t on, uint16_t off) {
 void Adafruit_PWMServoDriver::setPin(uint8_t num, uint16_t val, bool invert)
 {
   // Clamp value between 0 and 4095 inclusive.
-  val = min(val, 4095);
+  val = min(val, (uint16_t)4095);
   if (invert) {
     if (val == 0) {
       // Special value for signal fully on.
@@ -162,17 +175,17 @@ void Adafruit_PWMServoDriver::setPin(uint8_t num, uint16_t val, bool invert)
 /*******************************************************************************************/
 
 uint8_t Adafruit_PWMServoDriver::read8(uint8_t addr) {
-  Wire.beginTransmission(_i2caddr);
-  Wire.write(addr);
-  Wire.endTransmission();
+  _i2c->beginTransmission(_i2caddr);
+  _i2c->write(addr);
+  _i2c->endTransmission();
 
-  Wire.requestFrom((uint8_t)_i2caddr, (uint8_t)1);
-  return Wire.read();
+  _i2c->requestFrom((uint8_t)_i2caddr, (uint8_t)1);
+  return _i2c->read();
 }
 
 void Adafruit_PWMServoDriver::write8(uint8_t addr, uint8_t d) {
-  Wire.beginTransmission(_i2caddr);
-  Wire.write(addr);
-  Wire.write(d);
-  Wire.endTransmission();
+  _i2c->beginTransmission(_i2caddr);
+  _i2c->write(addr);
+  _i2c->write(d);
+  _i2c->endTransmission();
 }

Adafruit_PWMServoDriver.h

@@ -23,7 +23,7 @@
 #else
  #include "WProgram.h"
 #endif
-
+#include "Wire.h"
 
 #define PCA9685_SUBADR1 0x2
 #define PCA9685_SUBADR2 0x3
@@ -50,6 +50,7 @@
 class Adafruit_PWMServoDriver {
  public:
   Adafruit_PWMServoDriver(uint8_t addr = 0x40);
+  Adafruit_PWMServoDriver(TwoWire *I2C, uint8_t addr = 0x40);
   void begin(void);
   void reset(void);
   void setPWMFreq(float freq);
@@ -58,6 +59,8 @@ class Adafruit_PWMServoDriver {
 
  private:
   uint8_t _i2caddr;
+  
+  TwoWire *_i2c;
 
   uint8_t read8(uint8_t addr);
   void write8(uint8_t addr, uint8_t d);

examples/pwmtest/pwmtest.ino

@@ -5,8 +5,8 @@
   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
+  These drivers use I2C to communicate, 2 pins are required to  
+  interface.
 
   Adafruit invests time and resources providing this open source code, 
   please support Adafruit and open-source hardware by purchasing 
@@ -23,17 +23,10 @@
 Adafruit_PWMServoDriver pwm = Adafruit_PWMServoDriver();
 // you can also call it with a different address you want
 //Adafruit_PWMServoDriver pwm = Adafruit_PWMServoDriver(0x41);
-
-#if defined(ARDUINO_ARCH_SAMD)  
-// for Zero, output on USB Serial console, remove line below if using programming port to program the Zero!
-   #define Serial SerialUSB
-#endif
+// you can also call it with a different address and I2C interface
+//Adafruit_PWMServoDriver pwm = Adafruit_PWMServoDriver(&Wire, 0x40);
 
 void setup() {
-#ifdef ESP8266
-  Wire.pins(2, 14);   // ESP8266 can use any two pins, such as SDA to #2 and SCL to #14
-#endif
-  
   Serial.begin(9600);
   Serial.println("16 channel PWM test!");
 
@@ -43,22 +36,17 @@ void setup() {
   // if you want to really speed stuff up, you can go into 'fast 400khz I2C' mode
   // some i2c devices dont like this so much so if you're sharing the bus, watch
   // out for this!
-#ifdef TWBR    
-  // save I2C bitrate
-  uint8_t twbrbackup = TWBR;
-  // must be changed after calling Wire.begin() (inside pwm.begin())
-  TWBR = 12; // upgrade to 400KHz!
-#endif
+  Wire.setClock(400000);
 }
 
 void loop() {
   // Drive each PWM in a 'wave'
   for (uint16_t i=0; i<4096; i += 8) {
-    #ifdef ESP8266
-    yield();
-    #endif
     for (uint8_t pwmnum=0; pwmnum < 16; pwmnum++) {
       pwm.setPWM(pwmnum, 0, (i + (4096/16)*pwmnum) % 4096 );
     }
+#ifdef ESP8266
+    yield();  // take a breather, required for ESP8266
+#endif
   }
-}
+}

examples/servo/servo.ino

@@ -4,9 +4,9 @@
 
   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
+  
+  These drivers use I2C to communicate, 2 pins are required to  
+  interface.
 
   Adafruit invests time and resources providing this open source code, 
   please support Adafruit and open-source hardware by purchasing 
@@ -23,6 +23,8 @@
 Adafruit_PWMServoDriver pwm = Adafruit_PWMServoDriver();
 // you can also call it with a different address you want
 //Adafruit_PWMServoDriver pwm = Adafruit_PWMServoDriver(0x41);
+// you can also call it with a different address and I2C interface
+//Adafruit_PWMServoDriver pwm = Adafruit_PWMServoDriver(&Wire, 0x40);
 
 // Depending on your servo make, the pulse width min and max may vary, you 
 // want these to be as small/large as possible without hitting the hard stop
@@ -42,7 +44,7 @@ void setup() {
 
   pwm.setPWMFreq(60);  // Analog servos run at ~60 Hz updates
 
-  yield();
+  delay(10);
 }
 
 // you can use this function if you'd like to set the pulse length in seconds