Inherit from Serial and use software buffers for TX and RX. This allows the UART peripherals to operate in a IRQ driven mode. Overrides most (but not all) stdio functions as Serial did

Dependencies:   Buffer

Fork of BufferedSerial by Sam Grove

Revision:
0:a977d0a3d81e
Child:
1:57a11fb5d529
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/BufferedSerial.h	Thu May 23 19:31:30 2013 +0000
@@ -0,0 +1,130 @@
+
+/**
+ * @file    BufferedSerial.h
+ * @brief   Software Buffer - Extends mbed Serial functionallity adding irq driven TX and RX
+ * @author  sam grove
+ * @version 1.0
+ * @see     
+ *
+ * Copyright (c) 2013
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef BUFFEREDSERIAL_H
+#define BUFFEREDSERIAL_H
+ 
+#include "mbed.h"
+#include "Buffer.h"
+
+/** A serial port (UART) for communication with other serial devices
+ *
+ * Can be used for Full Duplex communication, or Simplex by specifying
+ * one pin as NC (Not Connected)
+ *
+ * Example:
+ * @code
+ *  #include "mbed.h"
+ *  #include "BufferedSerial.h"
+ *
+ *  BufferedSerial pc(USBTX, USBRX);
+ *
+ *  int main()
+ *  {
+ *      pc.baud(115200);
+ *    
+ *      while(1)
+ *      {
+ *          Timer s;
+ *        
+ *          s.start();
+ *          pc.printf("Hello World - buff\n");
+ *          int buffered_time = s.read_us();
+ *          wait(0.1f); // give time for the buffer to empty
+ *        
+ *          s.reset();
+ *          printf("Hello World - poll\n");
+ *          int polled_time = s.read_us();
+ *          s.stop();
+ *          wait(0.1f); // give time for the buffer to empty
+ *        
+ *          pc.printf("printf buffered took %d us\n", buffered_time);
+ *          pc.printf("printf polled took %d us\n", polled_time);
+ *          wait(0.5f);
+ *      }
+ *  }
+ * @endcode
+ */
+
+/**
+ *  @class BufferedSerial
+ *  @brief Software buffers and interrupt driven tx and rx for Serial
+ */  
+class BufferedSerial : public Serial 
+{
+private:
+    Buffer <char> _rxbuf;
+    Buffer <char> _txbuf;
+ 
+    void rxIrq(void);
+    void txIrq(void);
+    
+public:
+    /** Create a BufferedSerial port, connected to the specified transmit and receive pins
+     *  @param tx Transmit pin
+     *  @param rx Receive pin
+     *  @note Either tx or rx may be specified as NC if unused
+     */
+    BufferedSerial(PinName tx, PinName rx, const char* name=NULL);
+    
+    /** Destroy a BufferedSerial port
+     */
+    virtual ~BufferedSerial(void);
+    
+    /** Check on how many bytes are in the rx buffer
+     *  @return 1 if something exists, 0 otherwise
+     */
+    virtual int readable(void);
+    
+    /** Check to see if the tx buffer has room
+     *  @return 1 always has room and can overwrite previous content if too small / slow
+     */
+    virtual int writeable(void);
+    
+    /** Get a single byte from the BufferedSerial Port.
+     *  Should check readable() before calling this.
+     *  @return A byte that came in on the Serial Port
+     */
+    virtual int getc(void);
+    
+    /** Write a single byte to the BufferedSerial Port.
+     *  @param c The byte to write to the Serial Port
+     *  @return The byte that was written to the Serial Port
+     */
+    virtual int putc(int c);
+    
+    /** Write a string to the BufferedSerial Port. Must be NULL terminated
+     *  @param s The string to write to the Serial Port
+     *  @return The number of bytes written to the Serial Port
+     */
+    virtual int puts(const char *s);
+    
+    /** Write a formatted string to the BufferedSerial Port.
+     *  @param format The string + format specifiers to write to the Serial Port
+     *  @return The number of bytes written to the Serial Port
+     */
+    virtual int printf(const char* format, ...);
+    
+};
+
+#endif