Changing Wire API to inherit from Stream.

Renaming send() to write(), receive() to read(), etc.

libraries/Wire/Wire.cpp

@@ -124,7 +124,7 @@ uint8_t TwoWire::endTransmission(void)
 // must be called in:
 // slave tx event callback
 // or after beginTransmission(address)
-void TwoWire::send(uint8_t data)
+void TwoWire::write(uint8_t data)
 {
   if(transmitting){
   // in master transmitter mode
@@ -147,12 +147,12 @@ void TwoWire::send(uint8_t data)
 // must be called in:
 // slave tx event callback
 // or after beginTransmission(address)
-void TwoWire::send(uint8_t* data, uint8_t quantity)
+void TwoWire::write(const uint8_t *data, size_t quantity)
 {
   if(transmitting){
   // in master transmitter mode
-    for(uint8_t i = 0; i < quantity; ++i){
-      send(data[i]);
+    for(size_t i = 0; i < quantity; ++i){
+      write(data[i]);
     }
   }else{
   // in slave send mode
@@ -164,23 +164,15 @@ void TwoWire::send(uint8_t* data, uint8_t quantity)
 // must be called in:
 // slave tx event callback
 // or after beginTransmission(address)
-void TwoWire::send(char* data)
+void TwoWire::write(const char *data)
 {
-  send((uint8_t*)data, strlen(data));
-}
-
-// must be called in:
-// slave tx event callback
-// or after beginTransmission(address)
-void TwoWire::send(int data)
-{
-  send((uint8_t)data);
+  write((uint8_t*)data, strlen(data));
 }
 
 // must be called in:
 // slave rx event callback
 // or after requestFrom(address, numBytes)
-uint8_t TwoWire::available(void)
+int TwoWire::available(void)
 {
   return rxBufferLength - rxBufferIndex;
 }
@@ -188,11 +180,9 @@ uint8_t TwoWire::available(void)
 // must be called in:
 // slave rx event callback
 // or after requestFrom(address, numBytes)
-uint8_t TwoWire::receive(void)
+int TwoWire::read(void)
 {
-  // default to returning null char
-  // for people using with char strings
-  uint8_t value = '\0';
+  int value = -1;
   
   // get each successive byte on each call
   if(rxBufferIndex < rxBufferLength){
@@ -203,6 +193,25 @@ uint8_t TwoWire::receive(void)
   return value;
 }
 
+// must be called in:
+// slave rx event callback
+// or after requestFrom(address, numBytes)
+int TwoWire::peek(void)
+{
+  int value = -1;
+  
+  if(rxBufferIndex < rxBufferLength){
+    value = rxBuffer[rxBufferIndex];
+  }
+
+  return value;
+}
+
+void TwoWire::flush(void)
+{
+  // XXX: to be implemented.
+}
+
 // behind the scenes function that is called when data is received
 void TwoWire::onReceiveService(uint8_t* inBytes, int numBytes)
 {

libraries/Wire/Wire.h

@@ -21,10 +21,11 @@
 #define TwoWire_h
 
 #include <inttypes.h>
+#include "Stream.h"
 
 #define BUFFER_LENGTH 32
 
-class TwoWire
+class TwoWire : public Stream
 {
   private:
     static uint8_t rxBuffer[];
@@ -51,12 +52,13 @@ class TwoWire
     uint8_t endTransmission(void);
     uint8_t requestFrom(uint8_t, uint8_t);
     uint8_t requestFrom(int, int);
-    void send(uint8_t);
-    void send(uint8_t*, uint8_t);
-    void send(int);
-    void send(char*);
-    uint8_t available(void);
-    uint8_t receive(void);
+    virtual void write(uint8_t);
+    virtual void write(const char *);
+    virtual void write(const uint8_t *, size_t);
+    virtual int available(void);
+    virtual int read(void);
+    virtual int peek(void);
+	virtual void flush(void);
     void onReceive( void (*)(int) );
     void onRequest( void (*)(void) );
 };

libraries/Wire/examples/SFRRanger_reader/SFRRanger_reader.pde

@@ -26,8 +26,8 @@ void loop()
   Wire.beginTransmission(112); // transmit to device #112 (0x70)
                                // the address specified in the datasheet is 224 (0xE0)
                                // but i2c adressing uses the high 7 bits so it's 112
-  Wire.send(0x00);             // sets register pointer to the command register (0x00)  
-  Wire.send(0x50);             // command sensor to measure in "inches" (0x50) 
+  Wire.write(byte(0x00));      // sets register pointer to the command register (0x00)  
+  Wire.write(byte(0x50));      // command sensor to measure in "inches" (0x50) 
                                // use 0x51 for centimeters
                                // use 0x52 for ping microseconds
   Wire.endTransmission();      // stop transmitting
@@ -37,7 +37,7 @@ void loop()
 
   // step 3: instruct sensor to return a particular echo reading
   Wire.beginTransmission(112); // transmit to device #112
-  Wire.send(0x02);             // sets register pointer to echo #1 register (0x02)
+  Wire.write(byte(0x02));      // sets register pointer to echo #1 register (0x02)
   Wire.endTransmission();      // stop transmitting
 
   // step 4: request reading from sensor
@@ -46,9 +46,9 @@ void loop()
   // step 5: receive reading from sensor
   if(2 <= Wire.available())    // if two bytes were received
   {
-    reading = Wire.receive();  // receive high byte (overwrites previous reading)
+    reading = Wire.read();  // receive high byte (overwrites previous reading)
     reading = reading << 8;    // shift high byte to be high 8 bits
-    reading |= Wire.receive(); // receive low byte as lower 8 bits
+    reading |= Wire.read(); // receive low byte as lower 8 bits
     Serial.println(reading);   // print the reading
   }
 
@@ -64,23 +64,23 @@ void loop()
 void changeAddress(byte oldAddress, byte newAddress)
 {
   Wire.beginTransmission(oldAddress);
-  Wire.send(0x00);
-  Wire.send(0xA0);
+  Wire.write(byte(0x00));
+  Wire.write(byte(0xA0));
   Wire.endTransmission();
 
   Wire.beginTransmission(oldAddress);
-  Wire.send(0x00);
-  Wire.send(0xAA);
+  Wire.write(byte(0x00));
+  Wire.write(byte(0xAA));
   Wire.endTransmission();
 
   Wire.beginTransmission(oldAddress);
-  Wire.send(0x00);
-  Wire.send(0xA5);
+  Wire.write(byte(0x00));
+  Wire.write(byte(0xA5));
   Wire.endTransmission();
 
   Wire.beginTransmission(oldAddress);
-  Wire.send(0x00);
-  Wire.send(newAddress);
+  Wire.write(byte(0x00));
+  Wire.write(newAddress);
   Wire.endTransmission();
 }
 

libraries/Wire/examples/digital_potentiometer/digital_potentiometer.pde

@@ -25,8 +25,8 @@ void loop()
 {
   Wire.beginTransmission(44); // transmit to device #44 (0x2c)
                               // device address is specified in datasheet
-  Wire.send(0x00);            // sends instruction byte  
-  Wire.send(val);             // sends potentiometer value byte  
+  Wire.write(byte(0x00));            // sends instruction byte  
+  Wire.write(val);             // sends potentiometer value byte  
   Wire.endTransmission();     // stop transmitting
 
   val++;        // increment value

libraries/Wire/examples/master_reader/master_reader.pde

@@ -24,7 +24,7 @@ void loop()
 
   while(Wire.available())    // slave may send less than requested
   { 
-    char c = Wire.receive(); // receive a byte as character
+    char c = Wire.read(); // receive a byte as character
     Serial.print(c);         // print the character
   }
 

libraries/Wire/examples/master_writer/master_writer.pde

@@ -22,8 +22,8 @@ byte x = 0;
 void loop()
 {
   Wire.beginTransmission(4); // transmit to device #4
-  Wire.send("x is ");        // sends five bytes
-  Wire.send(x);              // sends one byte  
+  Wire.write("x is ");        // sends five bytes
+  Wire.write(x);              // sends one byte  
   Wire.endTransmission();    // stop transmitting
 
   x++;

libraries/Wire/examples/slave_receiver/slave_receiver.pde

@@ -30,9 +30,9 @@ void receiveEvent(int howMany)
 {
   while(1 < Wire.available()) // loop through all but the last
   {
-    char c = Wire.receive(); // receive byte as a character
+    char c = Wire.read(); // receive byte as a character
     Serial.print(c);         // print the character
   }
-  int x = Wire.receive();    // receive byte as an integer
+  int x = Wire.read();    // receive byte as an integer
   Serial.println(x);         // print the integer
 }

libraries/Wire/examples/slave_sender/slave_sender.pde

@@ -27,6 +27,6 @@ void loop()
 // this function is registered as an event, see setup()
 void requestEvent()
 {
-  Wire.send("hello "); // respond with message of 6 bytes
+  Wire.write("hello "); // respond with message of 6 bytes
                        // as expected by master
 }

libraries/Wire/utility/twi.c

@@ -232,7 +232,7 @@ uint8_t twi_writeTo(uint8_t address, uint8_t* data, uint8_t length, uint8_t wait
  *          2 not slave transmitter
  *          0 ok
  */
-uint8_t twi_transmit(uint8_t* data, uint8_t length)
+uint8_t twi_transmit(const uint8_t* data, uint8_t length)
 {
   uint8_t i;
 

libraries/Wire/utility/twi.h

@@ -46,7 +46,7 @@
   void twi_setAddress(uint8_t);
   uint8_t twi_readFrom(uint8_t, uint8_t*, uint8_t);
   uint8_t twi_writeTo(uint8_t, uint8_t*, uint8_t, uint8_t);
-  uint8_t twi_transmit(uint8_t*, uint8_t);
+  uint8_t twi_transmit(const uint8_t*, uint8_t);
   void twi_attachSlaveRxEvent( void (*)(uint8_t*, int) );
   void twi_attachSlaveTxEvent( void (*)(void) );
   void twi_reply(uint8_t);