Also check if TX buffer is empty before writing to data to UART reg directly

sandeepmistry · cmaglie · commit 610d4a8b8b10 · 2017-07-11T12:58:15.000+02:00
diff --git a/cores/arduino/Uart.cpp b/cores/arduino/Uart.cpp
@@ -107,7 +107,7 @@ int Uart::read()
 
 size_t Uart::write(const uint8_t data)
 {
-  if (sercom->isDataRegisterEmptyUART()) {
+  if (sercom->isDataRegisterEmptyUART() && txBuffer.available() == 0) {
     sercom->writeDataUART(data);
   } else {
     while(txBuffer.isFull()); // spin lock until a spot opens up in the buffer

Original file line number	Diff line number	Diff line change
`@@ -107,7 +107,7 @@ int Uart::read()`
`107`	`107`
`108`	`108`	`size_t Uart::write(const uint8_t data)`
`109`	`109`	`{`
`110`		`- if (sercom->isDataRegisterEmptyUART()) {`
	`110`	`+ if (sercom->isDataRegisterEmptyUART() && txBuffer.available() == 0) {`
`111`	`111`	`sercom->writeDataUART(data);`
`112`	`112`	`} else {`
`113`	`113`	`while(txBuffer.isFull()); // spin lock until a spot opens up in the buffer`