Change IRQ handler to check if data is available before check for DRE

sandeepmistry · cmaglie · commit 46653a61e18f · 2017-07-11T12:58:15.000+02:00
diff --git a/cores/arduino/Uart.cpp b/cores/arduino/Uart.cpp
@@ -62,6 +62,10 @@ void Uart::flush()
 
 void Uart::IrqHandler()
 {
+  if (sercom->availableDataUART()) {
+    rxBuffer.store_char(sercom->readDataUART());
+  }
+
   if (sercom->isDataRegisterEmptyUART()) {
     if (txBuffer.available()) {
       uint8_t data = txBuffer.read_char();
@@ -72,10 +76,6 @@ void Uart::IrqHandler()
     }
   }
 
-  if (sercom->availableDataUART()) {
-    rxBuffer.store_char(sercom->readDataUART());
-  }
-
   if (sercom->isUARTError()) {
     sercom->acknowledgeUARTError();
     // TODO: if (sercom->isBufferOverflowErrorUART()) ....

Original file line number	Diff line number	Diff line change
`@@ -62,6 +62,10 @@ void Uart::flush()`
`62`	`62`
`63`	`63`	`void Uart::IrqHandler()`
`64`	`64`	`{`
	`65`	`+ if (sercom->availableDataUART()) {`
	`66`	`+ rxBuffer.store_char(sercom->readDataUART());`
	`67`	`+ }`
	`68`	`+`
`65`	`69`	`if (sercom->isDataRegisterEmptyUART()) {`
`66`	`70`	`if (txBuffer.available()) {`
`67`	`71`	`uint8_t data = txBuffer.read_char();`
`@@ -72,10 +76,6 @@ void Uart::IrqHandler()`
`72`	`76`	`}`
`73`	`77`	`}`
`74`	`78`
`75`		`- if (sercom->availableDataUART()) {`
`76`		`- rxBuffer.store_char(sercom->readDataUART());`
`77`		`- }`
`78`		`-`
`79`	`79`	`if (sercom->isUARTError()) {`
`80`	`80`	`sercom->acknowledgeUARTError();`
`81`	`81`	`// TODO: if (sercom->isBufferOverflowErrorUART()) ....`