Added context switching and yield for cooperative multithreading.

1 files changed, 4 insertions, 2 deletions

diff --git a/usart.h b/usart.h
index 6c145c6..ab7fb3f 100644
--- a/usart.h
+++ b/usart.h
@@ -4,7 +4,7 @@
 template<>
 void interrupt<Interrupt::USART1>() {
 	USART1.DR;
-	GPIOA.ODR ^= 1 << 5;
+	//GPIOB.ODR ^= 1 << 1;
 }
 
 void usart_enable() {
@@ -16,7 +16,9 @@ void usart_enable() {
 }
 
 void usart_send(uint8_t data) {
-	while(!(USART1.SR & 0x80)); // Wait for TXE.
+	while(!(USART1.SR & 0x80)) {
+		Thread::yield();
+	} // Wait for TXE.
 	
 	USART1.DR = data;
 }