Add tag for the 120219 release.

[pub/USBasp.git] / Projects / USBtoSerial / USBtoSerial.c

diff --git a/Projects/USBtoSerial/USBtoSerial.c b/Projects/USBtoSerial/USBtoSerial.c
index 1dfd708..194f6b0 100644 (file)
--- a/Projects/USBtoSerial/USBtoSerial.c
+++ b/Projects/USBtoSerial/USBtoSerial.c
@@ -1,13 +1,13 @@
 /*
              LUFA Library
-     Copyright (C) Dean Camera, 2010.
+     Copyright (C) Dean Camera, 2012.
 
   dean [at] fourwalledcubicle [dot] com
            www.lufa-lib.org
 */
 
 /*
-  Copyright 2010  Dean Camera (dean [at] fourwalledcubicle [dot] com)
+  Copyright 2012  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
@@ -37,10 +37,16 @@
 #include "USBtoSerial.h"
 
 /** Circular buffer to hold data from the host before it is sent to the device via the serial port. */
-RingBuff_t USBtoUSART_Buffer;
+static RingBuffer_t USBtoUSART_Buffer;
+
+/** Underlying data buffer for \ref USBtoUSART_Buffer, where the stored bytes are located. */
+static uint8_t      USBtoUSART_Buffer_Data[128];
 
 /** Circular buffer to hold data from the serial port before it is sent to the host. */
-RingBuff_t USARTtoUSB_Buffer;
+static RingBuffer_t USARTtoUSB_Buffer;
+
+/** Underlying data buffer for \ref USARTtoUSB_Buffer, where the stored bytes are located. */
+static uint8_t      USARTtoUSB_Buffer_Data[128];
 
 /** LUFA CDC Class driver interface configuration and state information. This structure is
  *  passed to all CDC Class driver functions, so that multiple instances of the same class
@@ -66,6 +72,7 @@ USB_ClassInfo_CDC_Device_t VirtualSerial_CDC_Interface =
                        },
        };
 
+
 /** Main program entry point. This routine contains the overall program flow, including initial
  *  setup of all components and the main program loop.
  */
@@ -73,8 +80,8 @@ int main(void)
 {
        SetupHardware();
 
-       RingBuffer_InitBuffer(&USBtoUSART_Buffer);
-       RingBuffer_InitBuffer(&USARTtoUSB_Buffer);
+       RingBuffer_InitBuffer(&USBtoUSART_Buffer, USBtoUSART_Buffer_Data, sizeof(USBtoUSART_Buffer_Data));
+       RingBuffer_InitBuffer(&USARTtoUSB_Buffer, USARTtoUSB_Buffer_Data, sizeof(USARTtoUSB_Buffer_Data));
 
        LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
        sei();
@@ -90,22 +97,32 @@ int main(void)
                        if (!(ReceivedByte < 0))
                          RingBuffer_Insert(&USBtoUSART_Buffer, ReceivedByte);
                }
-               
+
                /* Check if the UART receive buffer flush timer has expired or the buffer is nearly full */
-               RingBuff_Count_t BufferCount = RingBuffer_GetCount(&USARTtoUSB_Buffer);
-               if ((TIFR0 & (1 << TOV0)) || (BufferCount > 200))
+               uint16_t BufferCount = RingBuffer_GetCount(&USARTtoUSB_Buffer);
+               if ((TIFR0 & (1 << TOV0)) || (BufferCount > (uint8_t)(sizeof(USARTtoUSB_Buffer_Data) * .75)))
                {
                        /* Clear flush timer expiry flag */
                        TIFR0 |= (1 << TOV0);
 
                        /* Read bytes from the USART receive buffer into the USB IN endpoint */
                        while (BufferCount--)
-                         CDC_Device_SendByte(&VirtualSerial_CDC_Interface, RingBuffer_Remove(&USARTtoUSB_Buffer));
+                       {
+                               /* Try to send the next byte of data to the host, abort if there is an error without dequeuing */
+                               if (CDC_Device_SendByte(&VirtualSerial_CDC_Interface,
+                                                       RingBuffer_Peek(&USARTtoUSB_Buffer)) != ENDPOINT_READYWAIT_NoError)
+                               {
+                                       break;
+                               }
+
+                               /* Dequeue the already sent byte from the buffer now we have confirmed that no transmission error occurred */
+                               RingBuffer_Remove(&USARTtoUSB_Buffer);
+                       }
                }
 
                /* Load the next byte from the USART transmit buffer into the USART */
                if (!(RingBuffer_IsEmpty(&USBtoUSART_Buffer)))
-                 Serial_TxByte(RingBuffer_Remove(&USBtoUSART_Buffer));
+                 Serial_SendByte(RingBuffer_Remove(&USBtoUSART_Buffer));
 
                CDC_Device_USBTask(&VirtualSerial_CDC_Interface);
                USB_USBTask();