Merge pull request #49 from arduino/1200bps-touch

Implemented Auto-Reset on 1200bps-touch (Native Port) to restart bootloader

boards.txt

@@ -28,8 +28,8 @@ arduino_zero_native.pid.0=0x004d
 arduino_zero_native.upload.tool=bossac
 arduino_zero_native.upload.protocol=sam-ba
 arduino_zero_native.upload.maximum_size=262144
-arduino_zero_native.upload.use_1200bps_touch=false
-arduino_zero_native.upload.wait_for_upload_port=false
+arduino_zero_native.upload.use_1200bps_touch=true
+arduino_zero_native.upload.wait_for_upload_port=true
 arduino_zero_native.upload.native_usb=true
 arduino_zero_native.build.mcu=cortex-m0plus
 arduino_zero_native.build.f_cpu=48000000L

cores/arduino/Reset.cpp

@@ -23,12 +23,28 @@
 extern "C" {
 #endif
 
+#define NVM_MEMORY ((volatile uint16_t *)0x000000)
+#define APP_START 0x00002004
+
+static inline bool nvmReady(void) {
+        return NVMCTRL->INTFLAG.reg & NVMCTRL_INTFLAG_READY;
+}
+
 __attribute__ ((long_call, section (".ramfunc")))
 static void banzai() {
 	// Disable all interrupts
 	__disable_irq();
 
-  // Reset the device
+	// Erase application
+	while (!nvmReady())
+		;
+	NVMCTRL->STATUS.reg |= NVMCTRL_STATUS_MASK;
+	NVMCTRL->ADDR.reg  = (uintptr_t)&NVM_MEMORY[APP_START / 4];
+	NVMCTRL->CTRLA.reg = NVMCTRL_CTRLA_CMD_ER | NVMCTRL_CTRLA_CMDEX_KEY;
+	while (!nvmReady())
+		;
+
+	// Reset the device
 	NVIC_SystemReset() ;
 
 	while (true);

cores/arduino/USB/CDC.cpp

@@ -119,21 +119,25 @@ bool WEAK CDC_Setup(Setup& setup)
 		if (CDC_SET_LINE_CODING == r)
 		{
 			USBD_RecvControl((void*)&_usbLineInfo,7);
-			return false;
 		}
 
 		if (CDC_SET_CONTROL_LINE_STATE == r)
 		{
 			_usbLineInfo.lineState = setup.wValueL;
+		}
+
+		if (CDC_SET_LINE_CODING == r || CDC_SET_CONTROL_LINE_STATE == r)
+		{
 			// auto-reset into the bootloader is triggered when the port, already
-			// open at 1200 bps, is closed.
-			if (1200 == _usbLineInfo.dwDTERate)
+			// open at 1200 bps, is closed. We check DTR state to determine if host 
+			// port is open (bit 0 of lineState).
+			if (1200 == _usbLineInfo.dwDTERate && (_usbLineInfo.lineState & 0x01) == 0)
+			{
+				initiateReset(250);
+			}
+			else
 			{
-				// We check DTR state to determine if host port is open (bit 0 of lineState).
-				if ((_usbLineInfo.lineState & 0x01) == 0)
-					initiateReset(250);
-				else
-					cancelReset();
+				cancelReset();
 			}
 			return false;
 		}

cores/arduino/delay.c

@@ -58,10 +58,13 @@ void delay( uint32_t ms )
   } while ( _ulTickCount - start <= ms ) ;
 }
 
+#include "Reset.h" // for tickReset()
+
 void SysTick_Handler( void )
 {
   // Increment tick count each ms
   _ulTickCount++ ;
+  tickReset();
 }
 
 #ifdef __cplusplus