Richard Osterloh / SerialDriver

RTOS safe buffered serial driver

Fork of SerialDriver by BlazeX .

SerialDriver.cpp@4:3c0d0c37ad75, 2015-02-23 (annotated)

Committer:
rosterloh84
Date:
Mon Feb 23 13:06:32 2015 +0000
Revision:
4:3c0d0c37ad75
Parent:
3:ea9719695b6a 
Added tx and rx overflow callback and message complete callback

Who changed what in which revision?

UserRevisionLine numberNew contents of line
BlazeX 0:cd0d79be0c1a 1 #include "SerialDriver.h"
BlazeX 0:cd0d79be0c1a 2
BlazeX 0:cd0d79be0c1a 3 SerialDriver::SerialDriver(PinName txPin, PinName rxPin, int txBufferLength_, int rxBufferLength_, unsigned char * txBuffer_, unsigned char * rxBuffer_)
BlazeX 0:cd0d79be0c1a 4 : SerialBase(txPin, rxPin), semTxBufferFull(0), semRxBufferEmpty(0)
BlazeX 0:cd0d79be0c1a 5 {
BlazeX 0:cd0d79be0c1a 6 // check buffer length
BlazeX 0:cd0d79be0c1a 7 txBufferLength= txBufferLength_;
BlazeX 0:cd0d79be0c1a 8 if(txBufferLength <= 1)
BlazeX 0:cd0d79be0c1a 9 error("TX buffer length must be > 1 !");
BlazeX 0:cd0d79be0c1a 10
BlazeX 0:cd0d79be0c1a 11 rxBufferLength= rxBufferLength_;
BlazeX 0:cd0d79be0c1a 12 if(rxBufferLength <= 1)
BlazeX 0:cd0d79be0c1a 13 error("RX buffer length must be > 1 !");
BlazeX 0:cd0d79be0c1a 14
BlazeX 0:cd0d79be0c1a 15 // take or allocate buffer
BlazeX 0:cd0d79be0c1a 16 txBuffer= txBuffer_;
BlazeX 0:cd0d79be0c1a 17 if(txBuffer == NULL)
BlazeX 0:cd0d79be0c1a 18 {
BlazeX 0:cd0d79be0c1a 19 txBuffer= new unsigned char[txBufferLength];
BlazeX 0:cd0d79be0c1a 20 if(txBuffer == NULL)
BlazeX 0:cd0d79be0c1a 21 error("Cannot allocate TX buffer!");
BlazeX 0:cd0d79be0c1a 22 }
BlazeX 0:cd0d79be0c1a 23
BlazeX 0:cd0d79be0c1a 24 rxBuffer= rxBuffer_;
BlazeX 0:cd0d79be0c1a 25 if(rxBuffer == NULL)
BlazeX 0:cd0d79be0c1a 26 {
BlazeX 0:cd0d79be0c1a 27 rxBuffer= new unsigned char[rxBufferLength];
BlazeX 0:cd0d79be0c1a 28 if(rxBuffer == NULL)
BlazeX 0:cd0d79be0c1a 29 error("Cannot allocate RX buffer!");
BlazeX 0:cd0d79be0c1a 30 }
BlazeX 0:cd0d79be0c1a 31
BlazeX 0:cd0d79be0c1a 32
BlazeX 0:cd0d79be0c1a 33 // reset cursors
BlazeX 0:cd0d79be0c1a 34 txIn= txOut= 0;
BlazeX 0:cd0d79be0c1a 35 rxIn= rxOut= 0;
BlazeX 0:cd0d79be0c1a 36 txCount= rxCount= 0;
BlazeX 0:cd0d79be0c1a 37
BlazeX 3:ea9719695b6a 38 // reset drop counters
BlazeX 3:ea9719695b6a 39 numTxDrops= 0;
BlazeX 3:ea9719695b6a 40 numRxDrops= 0;
BlazeX 3:ea9719695b6a 41
BlazeX 0:cd0d79be0c1a 42 // attach interrupt routines
BlazeX 0:cd0d79be0c1a 43 attach(this, &SerialDriver::onTxIrq, TxIrq);
BlazeX 0:cd0d79be0c1a 44 attach(this, &SerialDriver::onRxIrq, RxIrq);
BlazeX 0:cd0d79be0c1a 45 }
BlazeX 0:cd0d79be0c1a 46
BlazeX 0:cd0d79be0c1a 47 int SerialDriver::putc(int c, unsigned int timeoutMs)
BlazeX 0:cd0d79be0c1a 48 {
BlazeX 0:cd0d79be0c1a 49 // critical section, isr could modify cursors
BlazeX 0:cd0d79be0c1a 50 disableTxInterrupt();
BlazeX 0:cd0d79be0c1a 51
BlazeX 0:cd0d79be0c1a 52 if(isTxBufferFull())
BlazeX 0:cd0d79be0c1a 53 {
BlazeX 0:cd0d79be0c1a 54 // wait for free space
BlazeX 0:cd0d79be0c1a 55 while(semTxBufferFull.wait(0) > 0); // clear semaphore
BlazeX 0:cd0d79be0c1a 56 enableTxInterrupt();
BlazeX 0:cd0d79be0c1a 57
BlazeX 0:cd0d79be0c1a 58 // let isr work
BlazeX 0:cd0d79be0c1a 59 semTxBufferFull.wait(timeoutMs);
BlazeX 0:cd0d79be0c1a 60
BlazeX 0:cd0d79be0c1a 61 disableTxInterrupt();
BlazeX 0:cd0d79be0c1a 62 if(isTxBufferFull()) // still full? drop byte!
BlazeX 0:cd0d79be0c1a 63 {
BlazeX 3:ea9719695b6a 64 numTxDrops++;
BlazeX 0:cd0d79be0c1a 65 enableTxInterrupt();
BlazeX 0:cd0d79be0c1a 66 return 0;
BlazeX 0:cd0d79be0c1a 67 }
BlazeX 0:cd0d79be0c1a 68 }
BlazeX 0:cd0d79be0c1a 69
BlazeX 0:cd0d79be0c1a 70 // write this byte to tx buffer
BlazeX 0:cd0d79be0c1a 71 txBuffer[txIn]= (unsigned char)c;
BlazeX 0:cd0d79be0c1a 72 txIn= (txIn+1) % txBufferLength;
BlazeX 0:cd0d79be0c1a 73 txCount++;
BlazeX 0:cd0d79be0c1a 74
BlazeX 0:cd0d79be0c1a 75 // its over, isr can come
BlazeX 0:cd0d79be0c1a 76 enableTxInterrupt();
BlazeX 0:cd0d79be0c1a 77
BlazeX 0:cd0d79be0c1a 78 // Let's write (isr will check writeability itself)
BlazeX 0:cd0d79be0c1a 79 onTxIrq();
BlazeX 0:cd0d79be0c1a 80
BlazeX 0:cd0d79be0c1a 81 return 1;
BlazeX 0:cd0d79be0c1a 82 }
BlazeX 0:cd0d79be0c1a 83
BlazeX 0:cd0d79be0c1a 84 void SerialDriver::onTxIrq()
BlazeX 0:cd0d79be0c1a 85 {
BlazeX 0:cd0d79be0c1a 86 // prevent fire another TxIrq now
BlazeX 0:cd0d79be0c1a 87 disableTxInterrupt();
BlazeX 0:cd0d79be0c1a 88
BlazeX 0:cd0d79be0c1a 89 // write as long as you can
BlazeX 0:cd0d79be0c1a 90 bool wasFull= isTxBufferFull();
BlazeX 0:cd0d79be0c1a 91 while(SerialBase::writeable() && !isTxBufferEmtpy())
BlazeX 0:cd0d79be0c1a 92 {
BlazeX 0:cd0d79be0c1a 93 // take byte from tx buffer and put it out
BlazeX 0:cd0d79be0c1a 94 SerialBase::_base_putc(txBuffer[txOut]);
BlazeX 0:cd0d79be0c1a 95 txOut= (txOut+1) % txBufferLength;
BlazeX 0:cd0d79be0c1a 96 txCount--;
BlazeX 0:cd0d79be0c1a 97 }
BlazeX 0:cd0d79be0c1a 98
BlazeX 0:cd0d79be0c1a 99 if(wasFull && !isTxBufferFull()) // more bytes can come
BlazeX 0:cd0d79be0c1a 100 semTxBufferFull.release();
BlazeX 0:cd0d79be0c1a 101
BlazeX 0:cd0d79be0c1a 102 // ok, let's wait for next writability
BlazeX 0:cd0d79be0c1a 103 enableTxInterrupt();
BlazeX 0:cd0d79be0c1a 104 }
BlazeX 0:cd0d79be0c1a 105
BlazeX 0:cd0d79be0c1a 106
BlazeX 0:cd0d79be0c1a 107 int SerialDriver::getc(unsigned int timeoutMs)
BlazeX 0:cd0d79be0c1a 108 {
BlazeX 0:cd0d79be0c1a 109 // Let's read (isr will check readability itself)
BlazeX 0:cd0d79be0c1a 110 onRxIrq();
BlazeX 0:cd0d79be0c1a 111
BlazeX 0:cd0d79be0c1a 112 // critical section, isr could modify cursors
BlazeX 0:cd0d79be0c1a 113 disableRxInterrupt();
BlazeX 0:cd0d79be0c1a 114
BlazeX 0:cd0d79be0c1a 115 if(isRxBufferEmpty())
BlazeX 0:cd0d79be0c1a 116 {
BlazeX 0:cd0d79be0c1a 117 // wait for new byte
BlazeX 0:cd0d79be0c1a 118 while(semRxBufferEmpty.wait(0) > 0); // clear semaphore
BlazeX 0:cd0d79be0c1a 119 enableRxInterrupt();
BlazeX 0:cd0d79be0c1a 120
BlazeX 0:cd0d79be0c1a 121 // let isr work
BlazeX 0:cd0d79be0c1a 122 semRxBufferEmpty.wait(timeoutMs);
BlazeX 0:cd0d79be0c1a 123
BlazeX 0:cd0d79be0c1a 124 disableRxInterrupt();
BlazeX 0:cd0d79be0c1a 125 if(isRxBufferEmpty()) // still empty? nothing received!
BlazeX 0:cd0d79be0c1a 126 {
BlazeX 0:cd0d79be0c1a 127 enableRxInterrupt();
BlazeX 0:cd0d79be0c1a 128 return -1;
BlazeX 0:cd0d79be0c1a 129 }
BlazeX 0:cd0d79be0c1a 130 }
BlazeX 0:cd0d79be0c1a 131
BlazeX 0:cd0d79be0c1a 132 // get byte from rx buffer
BlazeX 0:cd0d79be0c1a 133 int c= (int)rxBuffer[rxOut];
BlazeX 0:cd0d79be0c1a 134 rxOut= (rxOut+1) % rxBufferLength;
BlazeX 0:cd0d79be0c1a 135 rxCount--;
BlazeX 0:cd0d79be0c1a 136
BlazeX 0:cd0d79be0c1a 137 // its over, isr can come
BlazeX 0:cd0d79be0c1a 138 enableRxInterrupt();
BlazeX 0:cd0d79be0c1a 139
BlazeX 0:cd0d79be0c1a 140 return c;
BlazeX 0:cd0d79be0c1a 141 }
BlazeX 0:cd0d79be0c1a 142
BlazeX 0:cd0d79be0c1a 143 void SerialDriver::onRxIrq()
BlazeX 0:cd0d79be0c1a 144 {
BlazeX 0:cd0d79be0c1a 145 // prevent fire another RxIrq now
BlazeX 0:cd0d79be0c1a 146 disableRxInterrupt();
BlazeX 0:cd0d79be0c1a 147
BlazeX 0:cd0d79be0c1a 148 // read as long as you can
BlazeX 0:cd0d79be0c1a 149 bool wasEmpty= isRxBufferEmpty();
BlazeX 0:cd0d79be0c1a 150 while(SerialBase::readable())
BlazeX 0:cd0d79be0c1a 151 {
BlazeX 0:cd0d79be0c1a 152 // get byte and store it to the RX buffer
BlazeX 0:cd0d79be0c1a 153 int c= SerialBase::_base_getc();
BlazeX 0:cd0d79be0c1a 154 if(!isRxBufferFull())
BlazeX 0:cd0d79be0c1a 155 {
BlazeX 0:cd0d79be0c1a 156 rxBuffer[rxIn]= (unsigned char)c;
BlazeX 0:cd0d79be0c1a 157 rxIn= (rxIn+1) % rxBufferLength;
BlazeX 0:cd0d79be0c1a 158 rxCount++;
rosterloh84 4:3c0d0c37ad75 159 if ('\n' == c) {
rosterloh84 4:3c0d0c37ad75 160 _callback_auto_detect.call();
rosterloh84 4:3c0d0c37ad75 161 }
BlazeX 3:ea9719695b6a 162 }
rosterloh84 4:3c0d0c37ad75 163 else { // drop byte :(
BlazeX 3:ea9719695b6a 164 numRxDrops++;
rosterloh84 4:3c0d0c37ad75 165 _callback_rx_overflow.call();
rosterloh84 4:3c0d0c37ad75 166 }
BlazeX 0:cd0d79be0c1a 167 }
BlazeX 0:cd0d79be0c1a 168
BlazeX 0:cd0d79be0c1a 169 if(wasEmpty && !isRxBufferEmpty()) // more bytes can go
BlazeX 0:cd0d79be0c1a 170 semRxBufferEmpty.release();
BlazeX 0:cd0d79be0c1a 171
BlazeX 0:cd0d79be0c1a 172 // ok, let's wait for next readability
BlazeX 0:cd0d79be0c1a 173 enableRxInterrupt();
BlazeX 0:cd0d79be0c1a 174 }
BlazeX 0:cd0d79be0c1a 175
BlazeX 0:cd0d79be0c1a 176
BlazeX 0:cd0d79be0c1a 177 int SerialDriver::write(const unsigned char * buffer, const unsigned int length, bool block)
BlazeX 0:cd0d79be0c1a 178 {
BlazeX 0:cd0d79be0c1a 179 // try to put all bytes
BlazeX 0:cd0d79be0c1a 180 for(int i= 0; i < length; i++)
BlazeX 0:cd0d79be0c1a 181 if(!putc(buffer[i], block ? osWaitForever : 0))
BlazeX 0:cd0d79be0c1a 182 return i; // putc failed, but already put i bytes
BlazeX 0:cd0d79be0c1a 183
BlazeX 0:cd0d79be0c1a 184 return length; // put all bytes
BlazeX 0:cd0d79be0c1a 185 }
BlazeX 0:cd0d79be0c1a 186
BlazeX 0:cd0d79be0c1a 187 int SerialDriver::read(unsigned char * buffer, const unsigned int length, bool block)
BlazeX 0:cd0d79be0c1a 188 {
BlazeX 0:cd0d79be0c1a 189 // try to get all bytes
BlazeX 0:cd0d79be0c1a 190 int c;
BlazeX 0:cd0d79be0c1a 191 for(int i= 0; i < length; i++)
BlazeX 0:cd0d79be0c1a 192 {
BlazeX 0:cd0d79be0c1a 193 c= getc(block ? osWaitForever : 0);
BlazeX 0:cd0d79be0c1a 194 if(c < 0)
BlazeX 0:cd0d79be0c1a 195 return i; // getc failed, but already got i bytes
BlazeX 0:cd0d79be0c1a 196 buffer[i]= (unsigned char)c;
BlazeX 0:cd0d79be0c1a 197 }
BlazeX 0:cd0d79be0c1a 198
BlazeX 0:cd0d79be0c1a 199 return length; // got all bytes
BlazeX 0:cd0d79be0c1a 200 }
BlazeX 0:cd0d79be0c1a 201
BlazeX 0:cd0d79be0c1a 202
BlazeX 0:cd0d79be0c1a 203 int SerialDriver::puts(const char * str, bool block)
BlazeX 0:cd0d79be0c1a 204 {
BlazeX 0:cd0d79be0c1a 205 // the same as write, but get length from strlen
BlazeX 0:cd0d79be0c1a 206 const int len= strlen(str);
BlazeX 0:cd0d79be0c1a 207 return write((const unsigned char *)str, len, block);
BlazeX 0:cd0d79be0c1a 208 }
BlazeX 0:cd0d79be0c1a 209
BlazeX 0:cd0d79be0c1a 210 int SerialDriver::printf(const char * format, ...)
BlazeX 0:cd0d79be0c1a 211 {
BlazeX 0:cd0d79be0c1a 212 // Parts of this are copied from mbed RawSerial ;)
BlazeX 0:cd0d79be0c1a 213 std::va_list arg;
BlazeX 0:cd0d79be0c1a 214 va_start(arg, format);
BlazeX 0:cd0d79be0c1a 215
BlazeX 0:cd0d79be0c1a 216 int length= vsnprintf(NULL, 0, format, arg);
BlazeX 0:cd0d79be0c1a 217 char *temp = new char[length + 1];
BlazeX 0:cd0d79be0c1a 218 vsprintf(temp, format, arg);
BlazeX 0:cd0d79be0c1a 219 puts(temp, true);
BlazeX 0:cd0d79be0c1a 220 delete[] temp;
BlazeX 0:cd0d79be0c1a 221
BlazeX 0:cd0d79be0c1a 222 va_end(arg);
BlazeX 0:cd0d79be0c1a 223 return length;
BlazeX 0:cd0d79be0c1a 224 }
BlazeX 0:cd0d79be0c1a 225
BlazeX 3:ea9719695b6a 226 // still thinking of XTN