Reduce code duplication for timeout handling in twi.c

cores/arduino/USBAPI.h

@@ -65,6 +65,8 @@ class USBDevice_
 	void detach();	// Serial port goes down too...
 	void poll();
 	bool wakeupHost(); // returns false, when wakeup cannot be processed
+
+	bool isSuspended();
 };
 extern USBDevice_ USBDevice;
 

cores/arduino/USBCore.cpp

@@ -855,4 +855,10 @@ bool USBDevice_::wakeupHost()
 	return false;
 }
 
+bool USBDevice_::isSuspended()
+{
+	return (_usbSuspendState & (1 << SUSPI));
+}
+
+
 #endif /* if defined(USBCON) */

cores/arduino/WInterrupts.c

@@ -65,7 +65,6 @@ static volatile voidFuncPtr intFunc[EXTERNAL_NUM_INTERRUPTS] = {
     nothing,
 #endif
 };
-// volatile static voidFuncPtr twiIntFunc;
 
 void attachInterrupt(uint8_t interruptNum, void (*userFunc)(void), int mode) {
   if(interruptNum < EXTERNAL_NUM_INTERRUPTS) {
@@ -274,11 +273,6 @@ void detachInterrupt(uint8_t interruptNum) {
   }
 }
 
-/*
-void attachInterruptTwi(void (*userFunc)(void) ) {
-  twiIntFunc = userFunc;
-}
-*/
 
 #define IMPLEMENT_ISR(vect, interrupt) \
   ISR(vect) { \
@@ -314,11 +308,3 @@ IMPLEMENT_ISR(INT2_vect, EXTERNAL_INT_2)
 #endif
 
 #endif
-
-/*
-ISR(TWI_vect) {
-  if(twiIntFunc)
-    twiIntFunc();
-}
-*/
-

libraries/Wire/src/Wire.cpp

@@ -15,7 +15,7 @@
   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
- 
+
   Modified 2012 by Todd Krein ([email protected]) to implement repeated starts
   Modified 2017 by Chuck Todd ([email protected]) to correct Unconfigured Slave Mode reboot
 */
@@ -86,24 +86,29 @@ void TwoWire::setClock(uint32_t clock)
   twi_setFrequency(clock);
 }
 
+void TwoWire::setTimeoutInMillis(uint8_t timeout)
+{
+  twi_setTimeoutInMillis(timeout);
+}
+
 uint8_t TwoWire::requestFrom(uint8_t address, uint8_t quantity, uint32_t iaddress, uint8_t isize, uint8_t sendStop)
 {
   if (isize > 0) {
-  // send internal address; this mode allows sending a repeated start to access
-  // some devices' internal registers. This function is executed by the hardware
-  // TWI module on other processors (for example Due's TWI_IADR and TWI_MMR registers)
+    // send internal address; this mode allows sending a repeated start to access
+    // some devices' internal registers. This function is executed by the hardware
+    // TWI module on other processors (for example Due's TWI_IADR and TWI_MMR registers)
 
-  beginTransmission(address);
+    beginTransmission(address);
 
-  // the maximum size of internal address is 3 bytes
-  if (isize > 3){
-    isize = 3;
-  }
+    // the maximum size of internal address is 3 bytes
+    if (isize > 3){
+      isize = 3;
+    }
 
-  // write internal register address - most significant byte first
-  while (isize-- > 0)
-    write((uint8_t)(iaddress >> (isize*8)));
-  endTransmission(false);
+    // write internal register address - most significant byte first
+    while (isize-- > 0)
+      write((uint8_t)(iaddress >> (isize*8)));
+    endTransmission(false);
   }
 
   // clamp to buffer length
@@ -158,8 +163,8 @@ void TwoWire::beginTransmission(int address)
 //	Originally, 'endTransmission' was an f(void) function.
 //	It has been modified to take one parameter indicating
 //	whether or not a STOP should be performed on the bus.
-//	Calling endTransmission(false) allows a sketch to 
-//	perform a repeated start. 
+//	Calling endTransmission(false) allows a sketch to
+//	perform a repeated start.
 //
 //	WARNING: Nothing in the library keeps track of whether
 //	the bus tenure has been properly ended with a STOP. It
@@ -202,7 +207,7 @@ size_t TwoWire::write(uint8_t data)
     // put byte in tx buffer
     txBuffer[txBufferIndex] = data;
     ++txBufferIndex;
-    // update amount in buffer   
+    // update amount in buffer
     txBufferLength = txBufferIndex;
   }else{
   // in slave send mode
@@ -244,7 +249,7 @@ int TwoWire::available(void)
 int TwoWire::read(void)
 {
   int value = -1;
-  
+
   // get each successive byte on each call
   if(rxBufferIndex < rxBufferLength){
     value = rxBuffer[rxBufferIndex];
@@ -260,7 +265,7 @@ int TwoWire::read(void)
 int TwoWire::peek(void)
 {
   int value = -1;
-  
+
   if(rxBufferIndex < rxBufferLength){
     value = rxBuffer[rxBufferIndex];
   }
@@ -289,7 +294,7 @@ void TwoWire::onReceiveService(uint8_t* inBytes, int numBytes)
   // copy twi rx buffer into local read buffer
   // this enables new reads to happen in parallel
   for(uint8_t i = 0; i < numBytes; ++i){
-    rxBuffer[i] = inBytes[i];    
+    rxBuffer[i] = inBytes[i];
   }
   // set rx iterator vars
   rxBufferIndex = 0;

libraries/Wire/src/Wire.h

@@ -54,6 +54,7 @@ class TwoWire : public Stream
     void begin(int);
     void end();
     void setClock(uint32_t);
+    void setTimeoutInMillis(uint8_t);
     void beginTransmission(uint8_t);
     void beginTransmission(int);
     uint8_t endTransmission(void);