--- a
+++ b/rx_ringbuffer.c
@@ -0,0 +1,62 @@
+/*
+Copyright (C) 2012 Georg Ottinger
+
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License
+as published by the Free Software Foundation; either version 2
+of the License, or (at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
+#include "includes.h"
+
+unsigned char rx_ring[256];
+unsigned char rx_head;
+unsigned char rx_tail;
+
+
+void InitRXBuffer()
+{
+  rx_head = 0;
+  rx_tail = 0;
+  ITC_SetSoftwarePriority(ITC_IRQ_UART2_RX, ITC_PRIORITYLEVEL_3);
+  UART2_ITConfig(UART2_IT_RXNE_OR, ENABLE);
+}
+
+#pragma vector = UART2_RX_vector
+__interrupt void UART_RX_vector(void)
+{
+  
+  rx_ring[rx_head] = UART2->DR;
+  
+  if(UART2_HasError())
+  {
+    rs232_rx_errors++;
+  } else { 
+    rx_head++;
+  }
+  
+}
+
+unsigned char RXBuffer_HasBytes()
+{
+  return rx_head - rx_tail;
+}
+
+unsigned char RXBuffer_ReadBytes()
+{
+  unsigned char temp;
+  
+  temp = rx_ring[rx_tail];
+  rx_tail++;
+ 
+  return temp;
+}