Create a new LightweightRingBuffer.h header file for the XPLAIN project to abstract out the new ring buffer without a performance penalty.

Projects/XPLAINBridge/Lib/LightweightRingBuff.h

@@ -0,0 +1,89 @@
+/*
+             LUFA Library
+     Copyright (C) Dean Camera, 2010.
+              
+  dean [at] fourwalledcubicle [dot] com
+      www.fourwalledcubicle.com
+*/
+
+/*
+  Copyright 2010  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
+  without fee, provided that the above copyright notice appear in 
+  all copies and that both that the copyright notice and this
+  permission notice and warranty disclaimer appear in supporting 
+  documentation, and that the name of the author not be used in 
+  advertising or publicity pertaining to distribution of the 
+  software without specific, written prior permission.
+
+  The author disclaim all warranties with regard to this
+  software, including all implied warranties of merchantability
+  and fitness.  In no event shall the author be liable for any
+  special, indirect or consequential damages or any damages
+  whatsoever resulting from loss of use, data or profits, whether
+  in an action of contract, negligence or other tortious action,
+  arising out of or in connection with the use or performance of
+  this software.
+*/
+
+/** \file
+ *
+ *  Ultra lightweight ring buffer, for fast insertion/deletion.
+ */
+ 
+#ifndef _ULW_RING_BUFF_H_
+#define _ULW_RING_BUFF_H_
+
+	/* Includes: */
+		#include <stdint.h>
+		#include <stdbool.h>
+
+	/* Defines: */
+		/** Size of each ring buffer, in bytes */
+		#define BUFFER_SIZE      128
+		
+		/** Type of data to store into the buffer */
+		#define RingBuff_Data_t  uint8_t
+
+	/* Type Defines: */
+		typedef struct
+		{
+			RingBuff_Data_t  Buffer[BUFFER_SIZE];
+			RingBuff_Data_t* In;
+			RingBuff_Data_t* Out;
+		} RingBuff_t;
+	
+	/* Inline Functions: */
+		static inline void RingBuffer_InitBuffer(RingBuff_t* const Buffer)
+		{
+			Buffer->In  = Buffer->Buffer;
+			Buffer->Out = Buffer->Buffer;		
+		}
+		
+		static inline void RingBuffer_Insert(RingBuff_t* const Buffer, RingBuff_Data_t Data)
+		{
+			*Buffer->In = Data;
+		
+			if (++Buffer->In == &Buffer->Buffer[BUFFER_SIZE])
+			  Buffer->In = Buffer->Buffer;
+		}
+
+		static inline RingBuff_Data_t RingBuffer_Remove(RingBuff_t* const Buffer)
+		{
+			RingBuff_Data_t Data = *Buffer->Out;
+		
+			if (++Buffer->Out == &Buffer->Buffer[BUFFER_SIZE])
+			  Buffer->Out = Buffer->Buffer;
+			  
+			return Data;
+		}
+
+		static inline bool RingBuffer_Empty(RingBuff_t* const Buffer)
+		{
+			return (Buffer->In == Buffer->Out);
+		}
+
+#endif
+ 

Projects/XPLAINBridge/XPLAINBridge.c

@@ -77,10 +77,8 @@ int main(void)
 {
 	SetupHardware();
 	
-	USBtoUART_Buffer.In  = USBtoUART_Buffer.Buffer;
-	USBtoUART_Buffer.Out = USBtoUART_Buffer.Buffer;
-	UARTtoUSB_Buffer.In  = UARTtoUSB_Buffer.Buffer;
-	UARTtoUSB_Buffer.Out = UARTtoUSB_Buffer.Buffer;
+	RingBuffer_InitBuffer(&USBtoUART_Buffer);
+	RingBuffer_InitBuffer(&UARTtoUSB_Buffer);
 	
 	LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
 	sei();
@@ -124,36 +122,19 @@ void USARTBridge_Task(void)
 
 	/* Read bytes from the USB OUT endpoint into the UART transmit buffer */
 	for (uint8_t DataBytesRem = CDC_Device_BytesReceived(&VirtualSerial_CDC_Interface); DataBytesRem != 0; DataBytesRem--)
-	{
-		*USBtoUART_Buffer.In = CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface);
-
-		if (++USBtoUART_Buffer.In == &USBtoUART_Buffer.Buffer[128])
-		  USBtoUART_Buffer.In = USBtoUART_Buffer.Buffer;
-	}
+	  RingBuffer_Insert(&USBtoUART_Buffer, CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface));
 	
 	/* Read bytes from the UART receive buffer into the USB IN endpoint */
-	if (UARTtoUSB_Buffer.In != UARTtoUSB_Buffer.Out)
-	{
-		CDC_Device_SendByte(&VirtualSerial_CDC_Interface, *UARTtoUSB_Buffer.Out);
-		if (++UARTtoUSB_Buffer.Out == &UARTtoUSB_Buffer.Buffer[128])
-		  UARTtoUSB_Buffer.Out = UARTtoUSB_Buffer.Buffer;
-	}
+	if (!(RingBuffer_Empty(&UARTtoUSB_Buffer)))
+	  CDC_Device_SendByte(&VirtualSerial_CDC_Interface, RingBuffer_Remove(&UARTtoUSB_Buffer));
 	
 	/* Load bytes from the UART transmit buffer into the UART */
-	if ((USBtoUART_Buffer.In != USBtoUART_Buffer.Out) && SoftUART_IsReady())
-	{
-		SoftUART_TxByte(*USBtoUART_Buffer.Out);
-		if (++USBtoUART_Buffer.Out == &USBtoUART_Buffer.Buffer[128])
-		  USBtoUART_Buffer.Out = USBtoUART_Buffer.Buffer;
-	}
+	if (!(RingBuffer_Empty(&USBtoUART_Buffer)) && SoftUART_IsReady())
+	  SoftUART_TxByte(RingBuffer_Remove(&USBtoUART_Buffer));
 	
 	/* Load bytes from the UART into the UART receive buffer */
 	if (SoftUART_IsReceived())
-	{
-		*UARTtoUSB_Buffer.In = SoftUART_RxByte();
-		if (++UARTtoUSB_Buffer.In == &UARTtoUSB_Buffer.Buffer[128])
-		  UARTtoUSB_Buffer.In = UARTtoUSB_Buffer.Buffer;		
-	}
+	  RingBuffer_Insert(&UARTtoUSB_Buffer, SoftUART_RxByte());
 
 	CDC_Device_USBTask(&VirtualSerial_CDC_Interface);
 }
@@ -183,7 +164,7 @@ void SetupHardware(void)
 	_delay_ms(10);
 
 	/* Select the firmware mode based on the JTD pin's value */
-	CurrentFirmwareMode = MODE_USART_BRIDGE; // TEMP (PINF & (1 << 7)) ? MODE_USART_BRIDGE : MODE_PDI_PROGRAMMER;
+	CurrentFirmwareMode = (PINF & (1 << 7)) ? MODE_USART_BRIDGE : MODE_PDI_PROGRAMMER;
 
 	/* Re-enable JTAG debugging */
 	MCUCR &= ~(1 << JTD);

Projects/XPLAINBridge/XPLAINBridge.h

@@ -45,8 +45,9 @@
 		#include "AVRISPDescriptors.h"
 		#include "USARTDescriptors.h"
 
-		#include "Lib/SoftUART.h"		
-		#include <Lib/V2Protocol.h>
+		#include "Lib/LightweightRingBuff.h"
+		#include "Lib/SoftUART.h"
+		#include "Lib/V2Protocol.h"
 
 		#include <LUFA/Version.h>
 		#include <LUFA/Drivers/Board/LEDs.h>
@@ -74,14 +75,6 @@
 
 		/** Firmware mode define for the AVRISP Programmer mode. */
 		#define MODE_PDI_PROGRAMMER      true
-		
-	/* Type Defines: */
-		typedef struct
-		{
-			uint8_t  Buffer[128];
-			uint8_t* In;
-			uint8_t* Out;
-		} RingBuff_t;
 
 	/* External Variables: */
 		extern bool CurrentFirmwareMode;