updated Wire library (from Arduino 1.6.6)

Author: ppescher

1.0.2/libraries/Wire/Wire.cpp

@@ -92,10 +92,11 @@ static inline bool TWI_STATUS_NACK(uint32_t status) {
 	return (status & TWI_SR_NACK) == TWI_SR_NACK;
 }
 
-TwoWire::TwoWire(Twi *_twi, void(*_beginCb)(void)) :
+TwoWire::TwoWire(Twi *_twi, void(*_beginCb)(void), void(*_endCb)(void)) :
 	twi(_twi), rxBufferIndex(0), rxBufferLength(0), txAddress(0),
 			txBufferLength(0), srvBufferIndex(0), srvBufferLength(0), status(
-					UNINITIALIZED), onBeginCallback(_beginCb), twiClock(TWI_CLOCK) {
+					UNINITIALIZED), onBeginCallback(_beginCb), 
+						onEndCallback(_endCb), twiClock(TWI_CLOCK) {
 }
 
 void TwoWire::begin(void) {
@@ -126,25 +127,37 @@ void TwoWire::begin(int address) {
 	begin((uint8_t) address);
 }
 
+void TwoWire::end(void) {
+	TWI_Disable(twi);
+
+	// Enable PDC channel
+	twi->TWI_PTCR &= ~(UART_PTCR_RXTDIS | UART_PTCR_TXTDIS);
+
+	if (onEndCallback)
+		onEndCallback();
+}
+
 void TwoWire::setClock(uint32_t frequency) {
 	twiClock = frequency;
 	TWI_SetClock(twi, twiClock, VARIANT_MCK);
 }
 
-uint8_t TwoWire::requestFrom(uint8_t address, uint8_t quantity, uint8_t sendStop) {
+uint8_t TwoWire::requestFrom(uint8_t address, uint8_t quantity, uint32_t iaddress, uint8_t isize, uint8_t sendStop) {
 	if (quantity > BUFFER_LENGTH)
 		quantity = BUFFER_LENGTH;
 
 	// perform blocking read into buffer
 	int readed = 0;
-	TWI_StartRead(twi, address, 0, 0);
+	TWI_StartRead(twi, address, iaddress, isize);
 	do {
 		// Stop condition must be set during the reception of last byte
 		if (readed + 1 == quantity)
 			TWI_SendSTOPCondition( twi);
 
-		TWI_WaitByteReceived(twi, RECV_TIMEOUT);
-		rxBuffer[readed++] = TWI_ReadByte(twi);
+		if (TWI_WaitByteReceived(twi, RECV_TIMEOUT))
+			rxBuffer[readed++] = TWI_ReadByte(twi);
+		else
+			break;
 	} while (readed < quantity);
 	TWI_WaitTransferComplete(twi, RECV_TIMEOUT);
 
@@ -155,6 +168,10 @@ uint8_t TwoWire::requestFrom(uint8_t address, uint8_t quantity, uint8_t sendStop
 	return readed;
 }
 
+uint8_t TwoWire::requestFrom(uint8_t address, uint8_t quantity, uint8_t sendStop) {
+	return requestFrom((uint8_t) address, (uint8_t) quantity, (uint32_t) 0, (uint8_t) 0, (uint8_t) sendStop);
+}
+
 uint8_t TwoWire::requestFrom(uint8_t address, uint8_t quantity) {
 	return requestFrom((uint8_t) address, (uint8_t) quantity, (uint8_t) true);
 }
@@ -315,27 +332,25 @@ void TwoWire::onService(void) {
 		}
 	}
 
-	if (status != SLAVE_IDLE) {
-		if (TWI_STATUS_TXCOMP(sr) && TWI_STATUS_EOSACC(sr)) {
-			if (status == SLAVE_RECV && onReceiveCallback) {
-				// Copy data into rxBuffer
-				// (allows to receive another packet while the
-				// user program reads actual data)
-				for (uint8_t i = 0; i < srvBufferLength; ++i)
-					rxBuffer[i] = srvBuffer[i];
-				rxBufferIndex = 0;
-				rxBufferLength = srvBufferLength;
-
-				// Alert calling program
-				onReceiveCallback( rxBufferLength);
-			}
-
-			// Transfer completed
-			TWI_EnableIt(twi, TWI_SR_SVACC);
-			TWI_DisableIt(twi, TWI_IDR_RXRDY | TWI_IDR_GACC | TWI_IDR_NACK
-					| TWI_IDR_EOSACC | TWI_IDR_SCL_WS | TWI_IER_TXCOMP);
-			status = SLAVE_IDLE;
+	if (status != SLAVE_IDLE && TWI_STATUS_EOSACC(sr)) {
+		if (status == SLAVE_RECV && onReceiveCallback) {
+			// Copy data into rxBuffer
+			// (allows to receive another packet while the
+			// user program reads actual data)
+			for (uint8_t i = 0; i < srvBufferLength; ++i)
+				rxBuffer[i] = srvBuffer[i];
+			rxBufferIndex = 0;
+			rxBufferLength = srvBufferLength;
+
+			// Alert calling program
+			onReceiveCallback( rxBufferLength);
 		}
+
+		// Transfer completed
+		TWI_EnableIt(twi, TWI_SR_SVACC);
+		TWI_DisableIt(twi, TWI_IDR_RXRDY | TWI_IDR_GACC | TWI_IDR_NACK
+				| TWI_IDR_EOSACC | TWI_IDR_SCL_WS | TWI_IER_TXCOMP);
+		status = SLAVE_IDLE;
 	}
 
 	if (status == SLAVE_RECV) {
@@ -375,7 +390,18 @@ static void Wire_Init(void) {
 	NVIC_EnableIRQ(WIRE_ISR_ID);
 }
 
-TwoWire Wire = TwoWire(WIRE_INTERFACE, Wire_Init);
+static void Wire_Deinit(void) {
+	NVIC_DisableIRQ(WIRE_ISR_ID);
+	NVIC_ClearPendingIRQ(WIRE_ISR_ID);
+
+	pmc_disable_periph_clk(WIRE_INTERFACE_ID);
+
+	// no need to undo PIO_Configure, 
+	// as Peripheral A was enable by default before,
+	// and pullups were not enabled
+}
+
+TwoWire Wire = TwoWire(WIRE_INTERFACE, Wire_Init, Wire_Deinit);
 
 void WIRE_ISR_HANDLER(void) {
 	Wire.onService();
@@ -402,7 +428,18 @@ static void Wire1_Init(void) {
 	NVIC_EnableIRQ(WIRE1_ISR_ID);
 }
 
-TwoWire Wire1 = TwoWire(WIRE1_INTERFACE, Wire1_Init);
+static void Wire1_Deinit(void) {
+	NVIC_DisableIRQ(WIRE1_ISR_ID);
+	NVIC_ClearPendingIRQ(WIRE1_ISR_ID);
+
+	pmc_disable_periph_clk(WIRE1_INTERFACE_ID);
+
+	// no need to undo PIO_Configure, 
+	// as Peripheral A was enable by default before,
+	// and pullups were not enabled
+}
+
+TwoWire Wire1 = TwoWire(WIRE1_INTERFACE, Wire1_Init, Wire1_Deinit);
 
 void WIRE1_ISR_HANDLER(void) {
 	Wire1.onService();

1.0.2/libraries/Wire/Wire.h

@@ -29,19 +29,24 @@
 
 #define BUFFER_LENGTH 32
 
+ // WIRE_HAS_END means Wire has end()
+#define WIRE_HAS_END 1
+
 class TwoWire : public Stream {
 public:
-	TwoWire(Twi *twi, void(*begin_cb)(void));
+	TwoWire(Twi *twi, void(*begin_cb)(void), void(*end_cb)(void));
 	void begin();
 	void begin(uint8_t);
 	void begin(int);
+	void end();
 	void setClock(uint32_t);
 	void beginTransmission(uint8_t);
 	void beginTransmission(int);
 	uint8_t endTransmission(void);
     uint8_t endTransmission(uint8_t);
 	uint8_t requestFrom(uint8_t, uint8_t);
     uint8_t requestFrom(uint8_t, uint8_t, uint8_t);
+	uint8_t requestFrom(uint8_t, uint8_t, uint32_t, uint8_t, uint8_t);
 	uint8_t requestFrom(int, int);
     uint8_t requestFrom(int, int, int);
 	virtual size_t write(uint8_t);
@@ -84,6 +89,9 @@ class TwoWire : public Stream {
 	// Called before initialization
 	void (*onBeginCallback)(void);
 
+	// Called after deinitialization
+	void (*onEndCallback)(void);
+
 	// TWI instance
 	Twi *twi;
 

1.0.2/libraries/Wire/library.properties

@@ -4,7 +4,7 @@ author=Arduino
 maintainer=Arduino <info@arduino.cc>
 sentence=Allows the communication between devices or sensors connected via Two Wire Interface Bus. For Arduino DUE only.
 paragraph=
-url=http://arduino.cc/en/Reference/Wire
+category=Communication
+url=http://www.arduino.cc/en/Reference/Wire
 architectures=sam
-types=Arduino