SerialBuffered.cpp

00001 
00002 #include "mbed.h"
00003 #include "SerialBuffered.h"
00004 
00005 SerialBuffered::SerialBuffered( PinName tx, PinName rx, size_t bufferSize ) : Serial(  tx,  rx ) 
00006 {
00007     m_buffSize = 0;
00008     m_contentStart = 0;
00009     m_contentEnd = 0;
00010     m_timeout = -1.0;
00011     _txpin = tx;
00012     _rxpin = rx;
00013     
00014     attach( this, &SerialBuffered::handleInterrupt );
00015     
00016     m_buff = (uint8_t *) malloc( bufferSize );
00017     if( m_buff )
00018         m_buffSize = bufferSize;
00019 }
00020 
00021 
00022 SerialBuffered::~SerialBuffered()
00023 {
00024     if( m_buff )
00025         free( m_buff );
00026 }
00027 
00028 void SerialBuffered::setTimeout( float seconds )
00029 {
00030     m_timeout = seconds;
00031 }
00032     
00033 size_t SerialBuffered::readBytes( uint8_t *bytes, size_t requested )
00034 {
00035     int i = 0;
00036 
00037     for( ; i < requested; )
00038     {
00039         int c = getc();
00040         if( c < 0 )
00041             break;
00042         bytes[i] = c;
00043         i++;
00044     }
00045     
00046     return i;
00047         
00048 }
00049 
00050 
00051 int SerialBuffered::_getc()
00052 {
00053     m_timer.reset();
00054     m_timer.start();
00055     while (m_contentStart == m_contentEnd) {
00056         if (m_timeout >= 0 &&  m_timer.read() >= m_timeout )
00057             return EOF;
00058         wait_ms( 1 );
00059     }
00060 
00061     m_timer.stop();
00062    
00063     int     nbp = (m_contentStart + 1) % m_buffSize;
00064     uint8_t result = m_buff[m_contentStart];
00065     m_contentStart = nbp;
00066     return result;    
00067 }
00068 
00069 //int Serial::_getc() {
00070 //    return _base_getc();
00071 //}
00072 
00073 int SerialBuffered::_putc(int c) {
00074     return _base_putc(c);
00075 }
00076 
00077 int SerialBuffered::readable()
00078 {
00079     return m_contentStart != m_contentEnd ;
00080 }
00081 
00082 void SerialBuffered::handleInterrupt()
00083 {
00084     while (serial_readable(&_serial)) {
00085         char c_in = _base_getc();
00086         int  nbp = (m_contentEnd + 1) % m_buffSize;
00087         
00088         if (nbp != m_contentStart) {
00089             m_buff[m_contentEnd] = c_in;
00090             m_contentEnd = nbp;
00091         }
00092     }
00093 }