From 742f59ac987294c2597cb42add725312c486681c Mon Sep 17 00:00:00 2001
From: Cristian Maglie <c.maglie@bug.st>
Date: Mon, 9 Jan 2012 18:53:46 +0100
Subject: [PATCH] Disable PDC controller during TWI init.

---
 hardware/sam/libraries/Wire/Wire.cpp | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/hardware/sam/libraries/Wire/Wire.cpp b/hardware/sam/libraries/Wire/Wire.cpp
index 146bda79d..67383ac3f 100644
--- a/hardware/sam/libraries/Wire/Wire.cpp
+++ b/hardware/sam/libraries/Wire/Wire.cpp
@@ -89,6 +89,10 @@ TwoWire::TwoWire(Twi *_twi, void(*_beginCb)(void)) :
 void TwoWire::begin(void) {
 	if (onBeginCallback)
 		onBeginCallback();
+
+	// Disable PDC channel
+	twi->TWI_PTCR = UART_PTCR_RXTDIS | UART_PTCR_TXTDIS;
+
 	TWI_ConfigureMaster(twi, TWI_CLOCK, VARIANT_MCK);
 	status = MASTER_IDLE;
 }
@@ -96,6 +100,10 @@ void TwoWire::begin(void) {
 void TwoWire::begin(uint8_t address) {
 	if (onBeginCallback)
 		onBeginCallback();
+
+	// Disable PDC channel
+	twi->TWI_PTCR = UART_PTCR_RXTDIS | UART_PTCR_TXTDIS;
+
 	TWI_ConfigureSlave(twi, address);
 	status = SLAVE_IDLE;
 	TWI_EnableIt(twi, TWI_IER_SVACC);