ATSerial.cpp

00001 #include "mbed.h"
00002 #include "ATSerial.h"
00003 #include "MTSLog.h"
00004 
00005 using namespace mts;
00006 
00007 ATSerial::ATSerial(PinName TXD, PinName RXD, int txBufferSize, int rxBufferSize)
00008     : MTSSerial(TXD, RXD, txBufferSize, rxBufferSize)
00009     , _serial(new RawSerial(TXD,RXD)),
00010     _baudrate(9600),
00011     _bits(8),
00012     _parity(mbed::SerialBase::None),
00013     _stop_bits(1),
00014     _last_time(0),
00015     _esc_cnt(0),
00016     _esc_ch('+'),
00017     _escaped(false)
00018 {
00019     timer.start();
00020     _serial->attach(this, &ATSerial::handleRead, Serial::RxIrq);
00021 }
00022 
00023 ATSerial::~ATSerial()
00024 {
00025     delete _serial;
00026 }
00027 
00028 
00029 
00030 void ATSerial::baud(int baudrate)
00031 {
00032     _baudrate = baudrate;
00033     _serial->baud(_baudrate);
00034 }
00035 
00036 void ATSerial::format(int bits, SerialBase::Parity parity, int stop_bits)
00037 {
00038     _bits = bits;
00039     _parity = parity;
00040     _stop_bits = stop_bits;
00041     _serial->format(_bits, _parity, _stop_bits);
00042 }
00043 
00044 void ATSerial::handleWrite()
00045 {
00046     while(txBuffer.size() != 0) {
00047         if (_serial->writeable()) {
00048             char byte;
00049             if(txBuffer.read(byte) == 1) {
00050                 _serial->attach(NULL, Serial::RxIrq);
00051                 _serial->putc(byte);
00052                 _serial->attach(this, &ATSerial::handleRead, Serial::RxIrq);
00053             }
00054         } else {
00055             return;
00056         }
00057     }
00058 }
00059 
00060 void mts::ATSerial::reattach(PinName TXD, PinName RXD) {
00061     delete _serial;
00062     _serial = new RawSerial(TXD, RXD);
00063     _serial->attach(this, &ATSerial::handleRead, Serial::RxIrq);
00064     _serial->baud(_baudrate);
00065     _serial->format(_bits, _parity, _stop_bits);
00066     rxBuffer.clear();
00067     txBuffer.clear();
00068 }
00069 
00070 void mts::ATSerial::sendBreak() {
00071     _serial->send_break();
00072 }
00073 
00074 bool ATSerial::escaped() {
00075 
00076     int now = timer.read_ms();
00077 
00078     // Have we seen three esc chars and 1 sec end guard has passed
00079     if (_escaped || (_esc_cnt == 3 && (now - _last_time > 1000))) {
00080         _escaped = true;
00081         return true;
00082 
00083     // Have we seen a couple esc chars but nothing in 500 ms
00084     } else if (_esc_cnt > 0 && _esc_cnt != 3 && now - _last_time > 500) {
00085         // Write seen esc chars
00086         while (_esc_cnt) {
00087             rxBuffer.write(_esc_ch);
00088             _esc_cnt--;
00089         }
00090     }
00091 
00092     return false;
00093 }
00094 
00095 void ATSerial::clearEscaped() {
00096     _esc_cnt = 0;
00097     _escaped = false;
00098 }
00099 
00100 void ATSerial::handleRead()
00101 {
00102     char byte = _serial->getc();
00103     int now = timer.read_ms();
00104 
00105     // Have we seen 3 esc chars but this char is before 1 sec end guard time
00106     if (_esc_cnt == 3 && (now - _last_time < 1000)) {
00107         // Write the three chars we held back
00108         while (_esc_cnt) {
00109             rxBuffer.write(_esc_ch);
00110             _esc_cnt--;
00111         }
00112     } else if (byte == _esc_ch) {
00113         // Has 1 second passed before last char
00114         if (now - _last_time > 1000) {
00115             _esc_cnt = 1;
00116         // Is this second or third esc char
00117         } else if (_esc_cnt > 0 && _esc_cnt < 3) {
00118             _esc_cnt++;
00119         }
00120     } else if (_esc_cnt > 0) {
00121         // Write any esc chars held back
00122         while (_esc_cnt) {
00123             rxBuffer.write(_esc_ch);
00124             _esc_cnt--;
00125         }
00126     }
00127 
00128     if(_esc_cnt == 0 && rxBuffer.write(byte) != 1) {
00129         // logError("Serial Rx Byte Dropped [%c][0x%02X]", byte, byte);
00130     }
00131 
00132     _last_time = timer.read_ms();
00133 }
00134 
00135 void ATSerial::escapeChar(char esc) {
00136     _esc_ch = esc;
00137 }
00138 
00139 char ATSerial::escapeChar() {
00140     return _esc_ch;
00141 }