From e9f8369ce8b464f178c778ff8bcc3f54fe70b30c Mon Sep 17 00:00:00 2001
From: Vegard Storheil Eriksen <zyp@jvnv.net>
Date: Sat, 3 Sep 2011 18:19:57 +0200
Subject: Added context switching and yield for cooperative multithreading.

---
 usart.h | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

(limited to 'usart.h')

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;
 }
-- 
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