Diff: RWDModule/RWDModule.cpp

Revision:

0:340078fc5139

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/RWDModule/RWDModule.cpp	Wed Jun 26 19:09:58 2013 +0000
@@ -0,0 +1,142 @@
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include "RWDModule.h"
+
+RWDModule::RWDModule(PinName tx, PinName rx, PinName cts) : m_serial(tx, rx), m_cts(cts),
+m_cmd(0), m_paramsBuf(NULL), m_respBuf(NULL), m_pos(0), m_paramsLen(0), m_respLen(0), m_ackOk(0), m_ackOkMask(0), m_ack(0), m_state(READY)
+{
+  //Setup baudrate
+  m_serial.baud(9600);
+  //Setup interrupts
+  m_serial.attach(this, &RWDModule::intTx, Serial::TxIrq); //Serial port writeable
+  m_serial.attach(this, &RWDModule::intRx, Serial::RxIrq); //Serial port readable
+  m_cts.fall(this, &RWDModule::intClearToSend); //Clear To Send: can send a command
+}
+
+void RWDModule::command(uint8_t cmd, const uint8_t* params, int paramsLen, uint8_t* resp, size_t respLen, uint8_t ackOk, size_t ackOkMask) //Ack Byte is not included in the resp buf
+{
+  if(!ready()) //If reader is not ready, does not submit another command yet
+    return;
+  
+  //Setup command
+  m_cmd = cmd;
+  
+  //Setup parameters
+  m_paramsBuf = (uint8_t*) params;
+  m_paramsLen = paramsLen;
+  
+  //Setup response
+  m_respBuf = resp;
+  m_respLen = respLen;
+  
+  //Pos in buf is 0
+  m_pos = 0;
+  
+  //Setup ack requirements
+  m_ackOk = ackOk;
+  m_ackOkMask = ackOkMask;
+  
+  m_state = CMD_QUEUED;
+}
+  
+bool RWDModule::ready()
+{
+  return (m_state==READY);
+}
+   
+bool RWDModule::result(uint8_t* pAck /*= NULL*/)
+{
+  if(!ready()) //Has command returned yet?
+    return false;
+  if(pAck) //If pointer is passed, return reader's ack
+    *pAck = m_ack;
+  return ((m_ack & m_ackOkMask) == m_ackOk); //Return whether the reader returned an error or OK ack
+}
+
+void RWDModule::intClearToSend()
+{
+  //Start sending command when Clear To Send falls
+  if(m_state == CMD_QUEUED) //Is there a command to be sent?
+  {
+    m_state = SENDING_CMD;
+    intTx(); //Start sending command
+  }
+}
+
+
+void RWDModule::intTx()
+{
+  if(m_state != SENDING_CMD)
+    return;  
+  if(m_pos==0) //Must send command-byte first
+    m_serial.putc((char)m_cmd);
+  while(true) //Send payload
+  {
+    if(m_pos >= m_paramsLen) //Payload sent completely?
+    {
+      m_pos = 0;
+      m_state = WAITING_FOR_ACK; //Next step
+      return;
+    }
+    m_serial.putc((char)m_paramsBuf[m_pos]); //Send payload byte
+    m_pos++;
+  }
+}
+
+void RWDModule::intRx()
+{
+  if(m_state == WAITING_FOR_ACK) //Get answer
+  {
+    m_ack = m_serial.getc(); //Get Ack
+    if( (m_ack & m_ackOkMask) != m_ackOk ) //Check if an error is returned
+    {
+      m_state = READY; //If yes, transfer is completed and result() will return false
+      return;
+    }
+    if(m_respLen)
+    {
+      m_state = RECEIVING_ACK; //Ack OK, now need to get response
+    }
+    else
+    {
+      m_state = READY; //Ack OK, end of transfer
+      return;
+    }
+  }
+  if(m_state != RECEIVING_ACK) //Error, should not happen
+  {
+    while(m_serial.readable())
+      m_serial.getc(); //Dump these bytes
+    return; 
+  }
+  while(m_serial.readable()) //Read payload
+  {
+    m_respBuf[m_pos] = (uint8_t) m_serial.getc(); //Read byte and put it in resp buf
+    m_pos++;
+    if(m_pos >= m_respLen)
+    {
+      m_pos = 0;
+      m_state = READY; //End of transfer, response retrieved with success
+    }
+  }
+}
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