arduino#1476 Extend API by adding a possibility to set a global timeout in milliseconds.

Author: wmarkow

hardware/arduino/avr/libraries/Wire/src/Wire.cpp

@@ -85,6 +85,11 @@ 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) {

hardware/arduino/avr/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);

hardware/arduino/avr/libraries/Wire/src/utility/twi.c

@@ -42,6 +42,7 @@ static volatile uint8_t twi_state;
 static volatile uint8_t twi_slarw;
 static volatile uint8_t twi_sendStop;			// should the transaction end with a stop
 static volatile uint8_t twi_inRepStart;			// in the middle of a repeated start
+static volatile uint8_t twi_timeout_ms = 0;
 
 static void (*twi_onSlaveTransmit)(void);
 static void (*twi_onSlaveReceive)(uint8_t*, int);
@@ -396,6 +397,11 @@ void twi_releaseBus(void)
   twi_state = TWI_READY;
 }
 
+void twi_setTimeoutInMillis(uint8_t timeout)
+{
+   twi_timeout_ms = timeout;
+}
+
 ISR(TWI_vect)
 {
   switch(TW_STATUS){

hardware/arduino/avr/libraries/Wire/src/utility/twi.h

@@ -50,6 +50,7 @@
   void twi_reply(uint8_t);
   void twi_stop(void);
   void twi_releaseBus(void);
+  void twi_setTimeoutInMillis(uint8_t);
 
 #endif