Revision 0:25b087be2989, committed 2012-03-17

Comitter:

chag

Date:

Sat Mar 17 17:25:55 2012 +0000

Commit message:

Changed in this revision

diff -r 000000000000 -r 25b087be2989 SoftwareSerial.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SoftwareSerial.cpp	Sat Mar 17 17:25:55 2012 +0000
@@ -0,0 +1,205 @@
+#include "mbed.h"
+#include "SoftwareSerial.h"
+
+namespace chag {
+
+/*unsigned char SoftwareSerial::inbuf[SOFTWARE_SERIAL_RX_BUFFER_SIZE];
+unsigned char SoftwareSerial::qin = 0;
+unsigned char SoftwareSerial::qout = 0;
+char SoftwareSerial::flag_rx_waiting_for_stop_bit;
+char SoftwareSerial::flag_rx_off;
+char SoftwareSerial::rx_mask;
+char SoftwareSerial::flag_rx_ready;
+char SoftwareSerial::flag_tx_ready;
+char SoftwareSerial::timer_rx_ctr;
+char SoftwareSerial::timer_tx_ctr;
+char SoftwareSerial::bits_left_in_rx;
+char SoftwareSerial::bits_left_in_tx;
+char SoftwareSerial::rx_num_of_bits;
+char SoftwareSerial::tx_num_of_bits;
+char SoftwareSerial::internal_rx_buffer;
+char SoftwareSerial::internal_tx_buffer;
+char SoftwareSerial::user_tx_buffer;
+*/
+
+DigitalOut led1(LED1);
+DigitalOut led2(LED2);
+DigitalOut led3(LED3);
+DigitalOut led4(LED4);
+
+
+SoftwareSerial::SoftwareSerial(PinName tx, PinName rx, const char *name) {
+    // save pins
+    
+    this->tx = (tx == NC) ? (DigitalOut *)NULL : new DigitalOut(tx);
+    this->rx = (rx == NC) ? (DigitalIn *)NULL : new DigitalIn(rx);
+    
+    flag_tx_ready = false;
+    flag_rx_ready = false;
+    flag_rx_waiting_for_stop_bit = false;
+    flag_rx_off = (rx == NC);
+    rx_num_of_bits = 10;
+    tx_num_of_bits = 10;
+
+    set_tx_pin_low();
+
+    baud(9600);
+}
+
+void SoftwareSerial::baud(int baudrate) {
+    baud_rate = baudrate;
+    ticker.detach();
+  
+    ticker.attach_us(this, &SoftwareSerial::timer_isr, 1000000.0 / (baudrate * 3.0));
+    
+    //timer_set( baud_rate );   //    Sets the timer to 3 times the baud rate.
+    //set_timer_interrupt( &SoftwareSerial::timer_isr );
+}
+
+// putc, etc
+
+int SoftwareSerial::readable() {
+    return( kbhit() );
+}
+
+int SoftwareSerial::writeable() {
+    return ( 1 );
+}
+
+// end
+
+
+int SoftwareSerial::get_rx_pin_status() {
+    //    Returns 0 or 1 dependent on whether the receive pin is high or low.
+    return( rx->read() );
+}
+
+void SoftwareSerial::set_tx_pin_high() {
+    //    Sets the transmit pin to the high state.
+    tx->write(1);
+    //led4 = 1;
+}
+
+void SoftwareSerial::set_tx_pin_low() {
+    //    Sets the transmit pin to the low state.
+    tx->write(0);
+    //led4 = 0;
+}
+
+void SoftwareSerial::idle() {
+    //    Background functions to execute while waiting for input.
+    
+}
+
+
+// protected/private members
+
+void SoftwareSerial::timer_isr( void ) {
+    char mask, start_bit, flag_in;
+
+    // Transmitter Section
+    if ( flag_tx_ready ) {
+        if( --timer_tx_ctr<=0 ) {
+            mask = internal_tx_buffer&1;
+            internal_tx_buffer >>= 1;
+            if ( mask ) {
+                set_tx_pin_high();
+            } else {
+                set_tx_pin_low();
+            }
+            timer_tx_ctr = 3;
+            if ( --bits_left_in_tx<=0 ) {
+                flag_tx_ready = false;
+            }
+        }
+    }
+    
+    // Receiver Section
+    if ( flag_rx_off==false ) {
+        if ( flag_rx_waiting_for_stop_bit ) {
+            if ( --timer_rx_ctr<=0 ) {
+                flag_rx_waiting_for_stop_bit = false;
+                flag_rx_ready = false;
+                internal_rx_buffer &= 0xFF;
+                if ( internal_rx_buffer!=0xC2 ) {
+                    inbuf[qin] = internal_rx_buffer;
+                    if ( ++qin>=SOFTWARE_SERIAL_RX_BUFFER_SIZE ) {
+                        qin = 0;
+                    }
+                }
+            }
+        } else {    // rx_test_busy
+            if ( flag_rx_ready==false ) {
+                start_bit = get_rx_pin_status();
+                // Test for Start Bit
+                if ( start_bit==0 ) {
+                    flag_rx_ready = true;
+                    internal_rx_buffer = 0;
+                    timer_rx_ctr = 4;
+                    bits_left_in_rx = rx_num_of_bits;
+                    rx_mask = 1;
+                }
+            } else {    // rx_busy
+                if ( --timer_rx_ctr<=0 ) {                // rcv
+                    timer_rx_ctr = 3;
+                    flag_in = get_rx_pin_status();
+                    if ( flag_in ) {
+                        internal_rx_buffer |= rx_mask;
+                    }
+                    rx_mask <<= 1;
+                    if ( --bits_left_in_rx<=0 ) {
+                        flag_rx_waiting_for_stop_bit = true;
+                    }
+                }
+            }
+        }
+    }
+}
+
+int SoftwareSerial::getc( void ) {
+    char        ch;
+
+    do {
+        while ( qout==qin ) {
+            idle();
+        }
+        ch = inbuf[qout] & 0xFF;
+        if ( ++qout>=SOFTWARE_SERIAL_RX_BUFFER_SIZE ) {
+            qout = 0;
+        }
+    } while ( ch==0x0A || ch==0xC2 );
+    return( (int)ch );
+}
+
+int SoftwareSerial::putc( int c ) {
+    led1 = !led1;
+    while ( flag_tx_ready );
+    user_tx_buffer = c;
+
+    // invoke_UART_transmit
+    timer_tx_ctr = 3;
+    bits_left_in_tx = tx_num_of_bits;
+    internal_tx_buffer = (user_tx_buffer<<1) | 0x200;
+    flag_tx_ready = true;
+    return(1);
+}
+
+void SoftwareSerial::flush_input_buffer( void ) {
+    qin = 0;
+    qout = 0;
+}
+
+char SoftwareSerial::kbhit( void ) {
+    return( qin!=qout );
+}
+
+void SoftwareSerial::turn_rx_on( void ) {
+    flag_rx_off = false;
+}
+
+void SoftwareSerial::turn_rx_off( void ) {
+    flag_rx_off = true;
+}
+
+
+} // end namespace
\ No newline at end of file

diff -r 000000000000 -r 25b087be2989 SoftwareSerial.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SoftwareSerial.h	Sat Mar 17 17:25:55 2012 +0000
@@ -0,0 +1,272 @@
+// modified from mbed library, original copyright:
+
+/* mbed Microcontroller Library - Serial
+ * Copyright (c) 2007-2011 ARM Limited. All rights reserved.
+ */ 
+
+
+#ifndef SOFTWARE_SERIAL_H
+#define SOFTWARE_SERIAL_H
+
+#ifndef SOFTWARE_SERIAL_RX_BUFFER_SIZE
+#define SOFTWARE_SERIAL_RX_BUFFER_SIZE 256
+#endif
+
+
+#include "mbed.h"
+
+
+namespace SoftwareSerial {
+
+/* Class: SoftwareSerial
+ *  A software implemented 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:
+ * > // Print "Hello World" to the PC
+ * >
+ * > #include "mbed.h"
+ * > #include "SoftwareSerial.h"
+ * >
+ * > SoftwareSerial ser(P19, P20);
+ * >
+ * > int main() {
+ * >     ser.printf("Hello World\n");
+ * > }
+ */
+class SoftwareSerial : public Stream {
+
+public:
+
+    /* Constructor: SoftwareSerial
+     *  Create a SoftwareSerial port, connected to the specified transmit and receive pins
+     *
+     * Variables:
+     *  tx - Transmit pin 
+     *  rx - Receive pin
+     *
+     *  Note: Either tx or rx may be specified as NC if unused
+     */
+    SoftwareSerial(PinName tx, PinName rx, const char *name = NULL);
+
+    /* Function: baud
+     *  Set the baud rate of the serial port
+     *  
+     * Variables:
+     *  baudrate - The baudrate of the serial port (default = 9600).
+     */
+    void baud(int baudrate);
+
+    /*enum Parity {
+        None = 0
+        , Odd
+        , Even
+        , Forced1    
+        , Forced0
+    };*/
+
+    enum IrqType {
+        RxIrq = 0
+        , TxIrq
+    };
+
+    /* Function: format
+     *  Set the transmission format used by the Serial port
+     *
+     * Variables:
+     *  bits - The number of bits in a word (5-8; default = 8)
+     *  parity - The parity used (SoftwareSerial::None, SoftwareSerial::Odd, SoftwareSerial::Even, SoftwareSerial::Forced1, SoftwareSerial::Forced0; default = SoftwareSerial::None)
+     *  stop - The number of stop bits (1 or 2; default = 1)
+     */
+    /*void format(int bits = 8, Parity parity = Serial::None, int stop_bits = 1); */
+
+#if 0 // Inhereted from Stream, for documentation only
+
+    /* Function: putc
+     *  Write a character
+     *
+     * Variables:
+     *  c - The character to write to the serial port
+     */
+    int putc(int c);
+
+
+    /* Function: getc
+     *  Read a character
+     *
+     * Reads a character from the serial port. This will block until 
+     * a character is available. To see if a character is available, 
+     * see <readable>
+     *
+     * Variables:
+     *  returns - The character read from the serial port
+     */
+    int getc();
+
+    /* Function: printf
+     *  Write a formated string
+     *
+     * Variables:
+     *  format - A printf-style format string, followed by the 
+     *      variables to use in formating the string.
+     */
+    int printf(const char* format, ...);
+
+    /* Function: scanf
+     *  Read a formated string 
+     *
+     * Variables:
+     *  format - A scanf-style format string,
+     *      followed by the pointers to variables to store the results. 
+     */
+    int scanf(const char* format, ...);
+ 
+#endif
+
+
+#if 1
+    /** putc
+     * @param int c The byte to write.
+     */
+    int  putc(int c);
+    
+    /** puts
+     * @param char * The string to print.
+     */
+    //void puts(char *s);
+    
+    /** getc
+     * @return int c The byte read or -1 if no bytes to read.
+     */
+    int  getc(void); 
+    
+    /** gets
+     * Get a string. Note, this method blocks until size bytes are read.
+     * @param char *s where to place the incoming bytes.
+     * @param int size How many bytes to read.
+     * @return char * The value of *s passed in.
+     */
+    //char *gets(char *s, int size);   
+    
+    /** peek
+     * like getc() but does NOT remove the byte from the buffer.
+     * @see getc*(
+     */
+    //int  peek(void);
+        
+#endif
+ 
+    /* Function: readable
+     *  Determine if there is a character available to read
+     *
+     * Variables:
+     *  returns - 1 if there is a character available to read, else 0
+     */
+    int readable();
+
+    /* Function: writeable
+     *  Determine if there is space available to write a character
+     * 
+     * Variables:
+     *  returns - 1 if there is space to write a character, else 0
+     */
+    int writeable();
+
+    /* Function: attach
+     *  Attach a function to call whenever a serial interrupt is generated
+     *
+     * Variables:
+     *  fptr - A pointer to a void function, or 0 to set as none
+     *  type - Which serial interrupt to attach the member function to (Seriall::RxIrq for receive, TxIrq for transmit buffer empty)
+     */
+    //void attach(void (*fptr)(void), IrqType type = RxIrq);
+
+    /* Function: attach
+     *  Attach a member function to call whenever a serial interrupt is generated
+     *     
+     * Variables:
+     *  tptr - pointer to the object to call the member function on
+     *  mptr - pointer to the member function to be called
+     *  type - Which serial interrupt to attach the member function to (Seriall::RxIrq for receive, TxIrq for transmit buffer empty)
+     */
+    template<typename T>
+    void attach(T* tptr, void (T::*mptr)(void), IrqType type = RxIrq) {
+        if((mptr != NULL) && (tptr != NULL)) {
+            _irq[type].attach(tptr, mptr);
+            setup_interrupt(type);
+        }
+    }
+
+#ifdef MBED_RPC
+    //virtual const struct rpc_method *get_rpc_methods();
+    static struct rpc_class *get_rpc_class();
+#endif
+
+protected:
+
+    //void setup_interrupt(IrqType type);
+    //void remove_interrupt(IrqType type);
+
+    //UARTName _uart;
+    //FunctionPointer _irq[2];
+    //int _uidx;
+    
+    virtual int _putc(int c) { return putc(c); }
+    virtual int _getc()      { return getc(); }
+    
+
+
+    int get_rx_pin_status();
+    void set_tx_pin_high();
+    void set_tx_pin_low();
+    void idle();
+    void timer_set( int baud );
+    void set_timer_interrupt( void (*timer_isr)(void) );
+  
+    
+    
+    void timer_isr( void );
+    void init_uart( void );
+    //char _getchar( void );
+    //void _putchar( char ch );
+    void flush_input_buffer( void );
+    char kbhit( void );
+    void turn_rx_on( void );
+    void turn_rx_off( void );
+    
+
+private:
+    DigitalOut *tx;
+    DigitalIn *rx;
+    
+    Ticker ticker;
+    
+    int baud_rate;
+
+    unsigned char inbuf[SOFTWARE_SERIAL_RX_BUFFER_SIZE];
+    unsigned char qin;
+    unsigned char qout;
+    char flag_rx_waiting_for_stop_bit;
+    bool flag_rx_off;
+    char rx_mask;
+    bool flag_rx_ready;
+    bool flag_tx_ready;
+    char timer_rx_ctr;
+    char timer_tx_ctr;
+    char bits_left_in_rx;
+    char bits_left_in_tx;
+    char rx_num_of_bits;
+    char tx_num_of_bits;
+    char internal_rx_buffer;
+    char internal_tx_buffer;
+    char user_tx_buffer;
+
+};
+
+} // namespace
+
+using namespace SoftwareSerial;
+
+#endif