X-Git-Url: http://git.linex4red.de/pub/USBasp.git/blobdiff_plain/eee252603be67c539f9986cde76454f756e55d95..3642ea0b9715cdf0196b10c9fc97898940eaefa6:/Projects/USBtoSerial/USBtoSerial.c

diff --git a/Projects/USBtoSerial/USBtoSerial.c b/Projects/USBtoSerial/USBtoSerial.c
index 5fd719224..266592b14 100644
--- a/Projects/USBtoSerial/USBtoSerial.c
+++ b/Projects/USBtoSerial/USBtoSerial.c
@@ -1,13 +1,13 @@
 /*
              LUFA Library
-     Copyright (C) Dean Camera, 2012.
+     Copyright (C) Dean Camera, 2015.
 
   dean [at] fourwalledcubicle [dot] com
            www.lufa-lib.org
 */
 
 /*
-  Copyright 2012  Dean Camera (dean [at] fourwalledcubicle [dot] com)
+  Copyright 2015  Dean Camera (dean [at] fourwalledcubicle [dot] com)
 
   Permission to use, copy, modify, distribute, and sell this
   software and its documentation for any purpose is hereby granted
@@ -56,7 +56,7 @@ USB_ClassInfo_CDC_Device_t VirtualSerial_CDC_Interface =
 	{
 		.Config =
 			{
-				.ControlInterfaceNumber         = 0,
+				.ControlInterfaceNumber         = INTERFACE_ID_CDC_CCI,
 				.DataINEndpoint                 =
 					{
 						.Address                = CDC_TX_EPADDR,
@@ -99,24 +99,20 @@ int main(void)
 		{
 			int16_t ReceivedByte = CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface);
 
-			/* Read bytes from the USB OUT endpoint into the USART transmit buffer */
+			/* Store received byte into the USART transmit buffer */
 			if (!(ReceivedByte < 0))
 			  RingBuffer_Insert(&USBtoUSART_Buffer, ReceivedByte);
 		}
 
-		/* Check if the UART receive buffer flush timer has expired or the buffer is nearly full */
 		uint16_t BufferCount = RingBuffer_GetCount(&USARTtoUSB_Buffer);
-		if ((TIFR0 & (1 << TOV0)) || (BufferCount > (uint8_t)(sizeof(USARTtoUSB_Buffer_Data) * .75)))
+		if (BufferCount)
 		{
 			Endpoint_SelectEndpoint(VirtualSerial_CDC_Interface.Config.DataINEndpoint.Address);
-			
+
 			/* Check if a packet is already enqueued to the host - if so, we shouldn't try to send more data
 			 * until it completes as there is a chance nothing is listening and a lengthy timeout could occur */
 			if (Endpoint_IsINReady())
 			{
-				/* Clear flush timer expiry flag */
-				TIFR0 |= (1 << TOV0);
-			
 				/* Never send more than one bank size less one byte to the host at a time, so that we don't block
 				 * while a Zero Length Packet (ZLP) to terminate the transfer is sent if the host isn't listening */
 				uint8_t BytesToSend = MIN(BufferCount, (CDC_TXRX_EPSIZE - 1));
@@ -137,8 +133,8 @@ int main(void)
 			}
 		}
 
-		/* Load the next byte from the USART transmit buffer into the USART */
-		if (!(RingBuffer_IsEmpty(&USBtoUSART_Buffer)))
+		/* Load the next byte from the USART transmit buffer into the USART if transmit buffer space is available */
+		if (Serial_IsSendReady() && !(RingBuffer_IsEmpty(&USBtoUSART_Buffer)))
 		  Serial_SendByte(RingBuffer_Remove(&USBtoUSART_Buffer));
 
 		CDC_Device_USBTask(&VirtualSerial_CDC_Interface);
@@ -149,19 +145,18 @@ int main(void)
 /** Configures the board hardware and chip peripherals for the demo's functionality. */
 void SetupHardware(void)
 {
+#if (ARCH == ARCH_AVR8)
 	/* Disable watchdog if enabled by bootloader/fuses */
 	MCUSR &= ~(1 << WDRF);
 	wdt_disable();
 
 	/* Disable clock division */
 	clock_prescale_set(clock_div_1);
+#endif
 
 	/* Hardware Initialization */
 	LEDs_Init();
 	USB_Init();
-
-	/* Start the flush timer so that overflows occur rapidly to push received bytes to the USB interface */
-	TCCR0B = (1 << CS02);
 }
 
 /** Event handler for the library USB Connection event. */
@@ -199,7 +194,7 @@ ISR(USART1_RX_vect, ISR_BLOCK)
 {
 	uint8_t ReceivedByte = UDR1;
 
-	if (USB_DeviceState == DEVICE_STATE_Configured)
+	if ((USB_DeviceState == DEVICE_STATE_Configured) && !(RingBuffer_IsFull(&USARTtoUSB_Buffer)))
 	  RingBuffer_Insert(&USARTtoUSB_Buffer, ReceivedByte);
 }
 
@@ -237,6 +232,9 @@ void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCI
 			break;
 	}
 
+	/* Keep the TX line held high (idle) while the USART is reconfigured */
+	PORTD |= (1 << 3);
+
 	/* Must turn off USART before reconfiguring it, otherwise incorrect operation may occur */
 	UCSR1B = 0;
 	UCSR1A = 0;
@@ -249,5 +247,8 @@ void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCI
 	UCSR1C = ConfigMask;
 	UCSR1A = (1 << U2X1);
 	UCSR1B = ((1 << RXCIE1) | (1 << TXEN1) | (1 << RXEN1));
+
+	/* Release the TX line after the USART has been reconfigured */
+	PORTD &= ~(1 << 3);
 }