Diff: BufferedSoftSerial.h

Revision:

6:4e3e18b41ea6

Child:

7:58d0adeb95aa

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/BufferedSoftSerial.h	Sat Apr 26 20:55:42 2014 +0000
@@ -0,0 +1,143 @@
+
+/**
+ * @file    BufferedSoftSerial.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 BUFFEREDSOFTSERIAL_H
+#define BUFFEREDSOFTSERIAL_H
+ 
+#include "mbed.h"
+#include "Buffer.h"
+#include "SoftSerial.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)
+ *
+ * This uses software serial emulation, regular serial pins are alot better,
+ * however if you don't have spare ones, you can use this. It is advicable
+ * to put the serial connection with highest speed to hardware serial.
+ *
+ * If you lack RAM memory you can also use SoftSerial without this buffer around it.
+ * In that case it is fully blocking.
+ *
+ * Example:
+ * @code
+ * #include "mbed.h"
+ * #include "BufferedSoftSerial.h"
+ * 
+ * BufferedSoftSerial buf(USBTX, USBRX);
+ * SoftSerial block(USBTX, USBRX);
+ * 
+ * int main()
+ * {
+ *     while(1) {
+ *         Timer s;
+ * 
+ *         s.start();
+ *         buf.printf("Hello World - buffered\r\n");
+ *         int buffered_time = s.read_us();
+ *         wait(0.1f); // give time for the buffer to empty
+ * 
+ *         s.reset();
+ *         block.printf("Hello World - blocking\r\n");
+ *         int polled_time = s.read_us();
+ *         s.stop();
+ *         wait(0.1f); // give time for the buffer to empty
+ * 
+ *         buf.printf("printf buffered took %d us\r\n", buffered_time);
+ *         buf.printf("printf blocking took %d us\r\n", polled_time);
+ *         wait(5);
+ *     }
+ * }
+ * @endcode
+ */
+
+/**
+ *  @class BufferedSerial
+ *  @brief Software buffers and interrupt driven tx and rx for SoftSerial
+ */  
+class BufferedSoftSerial : public SoftSerial 
+{
+private:
+    Buffer <char> _rxbuf;
+    Buffer <char> _txbuf;
+ 
+    void rxIrq(void);
+    void txIrq(void);
+    void prime(void);
+    
+public:
+    /** Create a BufferedSoftSerial 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
+     */
+    BufferedSoftSerial(PinName tx, PinName rx, const char* name=NULL);
+    
+    /** Destroy a BufferedSoftSerial port
+     */
+    virtual ~BufferedSoftSerial(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 BufferedSoftSerial Port.
+     *  Should check readable() before calling this.
+     *  @return A byte that came in on the BufferedSoftSerial Port
+     */
+    virtual int getc(void);
+    
+    /** Write a single byte to the BufferedSoftSerial Port.
+     *  @param c The byte to write to the BufferedSoftSerial Port
+     *  @return The byte that was written to the BufferedSoftSerial Port Buffer
+     */
+    virtual int putc(int c);
+    
+    /** Write a string to the BufferedSoftSerial 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 Buffer
+     */
+    virtual int puts(const char *s);
+    
+    /** Write a formatted string to the BufferedSoftSerial Port.
+     *  @param format The string + format specifiers to write to the BufferedSoftSerial Port
+     *  @return The number of bytes written to the Serial Port Buffer
+     */
+    virtual int printf(const char* format, ...);
+    
+    /** Write data to the BufferedSoftSerial Port
+     *  @param s A pointer to data to send
+     *  @param length The amount of data being pointed to
+     *  @return The number of bytes written to the Serial Port Buffer
+     */
+    virtual ssize_t write(const void *s, std::size_t length);
+};
+
+#endif