Alter the ring buffer library headers to have both atomic and non-atomic insertion...

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

diff --git a/Projects/USBtoSerial/USBtoSerial.c b/Projects/USBtoSerial/USBtoSerial.c
index 7a0f686..9189868 100644 (file)
--- a/Projects/USBtoSerial/USBtoSerial.c
+++ b/Projects/USBtoSerial/USBtoSerial.c
@@ -87,16 +87,22 @@ int main(void)
                        if (!(BUFFER_SIZE - USBtoUSART_Buffer.Count))
                          break;
                          
-                       RingBuffer_Insert(&USBtoUSART_Buffer, CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface));
+                       RingBuffer_AtomicInsert(&USBtoUSART_Buffer, CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface));
                }
                
-               /* Read bytes from the USART receive buffer into the USB IN endpoint */
-               while (USARTtoUSB_Buffer.Count)
-                 CDC_Device_SendByte(&VirtualSerial_CDC_Interface, RingBuffer_Remove(&USARTtoUSB_Buffer));
+               /* Check if the software USART flush timer has expired */
+               if (TIFR0 & (1 << TOV0))
+               {
+                       TIFR0 |= (1 << TOV0);
+
+                       /* Read bytes from the USART receive buffer into the USB IN endpoint */
+                       while (USARTtoUSB_Buffer.Count)
+                         CDC_Device_SendByte(&VirtualSerial_CDC_Interface, RingBuffer_AtomicRemove(&USARTtoUSB_Buffer));
+               }
                
-               /* Load bytes from the USART transmit buffer into the USART */
-               while (USBtoUSART_Buffer.Count)
-                 Serial_TxByte(RingBuffer_Remove(&USBtoUSART_Buffer));
+               /* Load the next byte from the USART transmit buffer into the USART */
+               if (USBtoUSART_Buffer.Count)
+                 Serial_TxByte(RingBuffer_AtomicRemove(&USBtoUSART_Buffer));
                
                CDC_Device_USBTask(&VirtualSerial_CDC_Interface);
                USB_USBTask();
@@ -117,6 +123,9 @@ void SetupHardware(void)
        Serial_Init(9600, false);
        LEDs_Init();
        USB_Init();
+
+       /* Configure the UART flush timer - run at Fcpu/1024 for maximum interval before overflow */
+       TCCR0B = ((1 << CS02) | (1 << CS00));
 }
 
 /** Event handler for the library USB Connection event. */