owllu.c

sdcc是为51等小型嵌入式cpu设计的c语言编译器支持数种不同类型的cpu

}

//--------------------------------------------------------------------------
// Set the 1-Wire Net communucation speed.  
//
// 'portnum'   - number 0 to MAX_PORTNUM-1.  This number was provided to
//               OpenCOM to indicate the port number.
// 'new_speed' - new speed defined as
//                MODE_NORMAL     0x00
//                MODE_OVERDRIVE  0x01
//
// Returns:  current 1-Wire Net speed 
//
int owSpeed(int portnum, int new_speed)
{
   uchar sendpacket[5];
   short sendlen=0;
   int rt = FALSE;
   
#if DEBUG_OW_LLU
   printf ("starting owSpeed: %d\n", new_speed);
#endif
   // check if change from current mode
   if (((new_speed == MODE_OVERDRIVE) &&
        (USpeed[portnum] != SPEEDSEL_OD)) ||
       ((new_speed == MODE_NORMAL) &&
        (USpeed[portnum] != SPEEDSEL_FLEX)))
   {
      if (new_speed == MODE_OVERDRIVE) 
      {
         // if overdrive then switch to 115200 baud
         if (DS2480ChangeBaud(portnum,PARMSET_115200) == PARMSET_115200)
         {
            USpeed[portnum] = SPEEDSEL_OD;
            rt = TRUE;
         }
      }
      else if (new_speed == MODE_NORMAL) 
      {
         // else normal so set to 9600 baud
         if (DS2480ChangeBaud(portnum,PARMSET_9600) == PARMSET_9600)
         {
            USpeed[portnum] = SPEEDSEL_FLEX;
            rt = TRUE;
         }
      }

      // if baud rate is set correctly then change DS2480 speed
      if (rt)
      {
         // check if correct mode 
         if (UMode[portnum] != MODSEL_COMMAND)
         {
            UMode[portnum] = MODSEL_COMMAND;
            sendpacket[sendlen++] = MODE_COMMAND;
         }

         // proceed to set the DS2480 communication speed
         sendpacket[sendlen++] = CMD_COMM | FUNCTSEL_SEARCHOFF | USpeed[portnum];

         // send the packet 
         if (!WriteCOM(portnum,sendlen,sendpacket)) 
         {
            rt = FALSE;
            // lost communication with DS2480 then reset 
            DS2480Detect(portnum);
         }
      }
   }
#if DEBUG_OW_LLU
   printf ("owSpeed: %d\n", rt);
#endif
   // return the current speed
   return (USpeed[portnum] == SPEEDSEL_OD) ? MODE_OVERDRIVE : MODE_NORMAL;
}

//--------------------------------------------------------------------------
// Set the 1-Wire Net line level.  The values for new_level are
// as follows:
//
// 'portnum'   - number 0 to MAX_PORTNUM-1.  This number was provided to
//               OpenCOM to indicate the port number.
// 'new_level' - new level defined as
//                MODE_NORMAL     0x00
//                MODE_STRONG5    0x02
//                MODE_PROGRAM    0x04
//                MODE_BREAK      0x08 (not supported)
//
// Returns:  current 1-Wire Net level  
//
int owLevel(int portnum, int new_level)
{
   uchar sendpacket[10],readbuffer[10];
   short sendlen=0;
   short rt=FALSE;

#if DEBUG_OW_LLU
   printf ("owLevel: %d\n", new_level);
#endif
   // check if need to change level
   if (new_level != ULevel[portnum])
   {
      // check if just putting back to normal
      if (new_level == MODE_NORMAL)
      {
         // check if correct mode 
         if (UMode[portnum] != MODSEL_COMMAND)
         {
            UMode[portnum] = MODSEL_COMMAND;
            sendpacket[sendlen++] = MODE_COMMAND;
         }

         // stop pulse command
         sendpacket[sendlen++] = MODE_STOP_PULSE;
   
         // flush the buffers
         FlushCOM(portnum);

         // send the packet 
         if (WriteCOM(portnum,sendlen,sendpacket)) 
         {
            // read back the 1 byte response 
            if (ReadCOM(portnum,1,readbuffer) == 1)
            {
               // check response byte
               if ((readbuffer[0] & 0xE0) == 0xE0)
               {
                  rt = TRUE;
                  ULevel[portnum] = MODE_NORMAL;
               }
            }
         }
      }
      // set new level
      else
      {
         // check if correct mode 
         if (UMode[portnum] != MODSEL_COMMAND)
         {
            UMode[portnum] = MODSEL_COMMAND;
            sendpacket[sendlen++] = MODE_COMMAND;
         }

         // strong 5 volts
         if (new_level == MODE_STRONG5)
         {
            // set the SPUD time value 
            sendpacket[sendlen++] = CMD_CONFIG | PARMSEL_5VPULSE | PARMSET_infinite;
            // add the command to begin the pulse
            sendpacket[sendlen++] = CMD_COMM | FUNCTSEL_CHMOD | SPEEDSEL_PULSE | BITPOL_5V;
         }
         // 12 volts
         else if (new_level == MODE_PROGRAM)
         {
            // check if programming voltage available
            if (!ProgramAvailable[portnum])
               return MODE_NORMAL;

            // set the PPD time value 
            sendpacket[sendlen++] = CMD_CONFIG | PARMSEL_12VPULSE | PARMSET_infinite;
            // add the command to begin the pulse
            sendpacket[sendlen++] = CMD_COMM | FUNCTSEL_CHMOD | SPEEDSEL_PULSE | BITPOL_12V;
         }

         // flush the buffers
         FlushCOM(portnum);

         // send the packet 
         if (WriteCOM(portnum,sendlen,sendpacket)) 
         {
            // read back the 1 byte response from setting time limit
            if (ReadCOM(portnum,1,readbuffer) == 1)
            {
               // check response byte
               if ((readbuffer[0] & 0x81) == 0)
               {
                  ULevel[portnum] = new_level;
                  rt = TRUE;
               }
            }
         }
      }

      // if lost communication with DS2480 then reset 
      if (rt != TRUE)
         DS2480Detect(portnum);
   }

   // return the current level
   return ULevel[portnum];      
}

//--------------------------------------------------------------------------
// This procedure creates a fixed 480 microseconds 12 volt pulse 
// on the 1-Wire Net for programming EPROM iButtons.
//
// 'portnum'  - number 0 to MAX_PORTNUM-1.  This number was provided to
//              OpenCOM to indicate the port number.
//
// Returns:  TRUE  successful
//           FALSE program voltage not available  
//
int owProgramPulse(int portnum)
{
   uchar sendpacket[10],readbuffer[10];
   short sendlen=0;

   // check if programming voltage available
   if (!ProgramAvailable[portnum])
      return FALSE;

   // make sure normal level
   owLevel(portnum,MODE_NORMAL);

   // check if correct mode 
   if (UMode[portnum] != MODSEL_COMMAND)
   {
      UMode[portnum] = MODSEL_COMMAND;
      sendpacket[sendlen++] = MODE_COMMAND;
   }

   // set the SPUD time value 
   sendpacket[sendlen++] = CMD_CONFIG | PARMSEL_12VPULSE | PARMSET_512us;

   // pulse command
   sendpacket[sendlen++] = CMD_COMM | FUNCTSEL_CHMOD | BITPOL_12V | SPEEDSEL_PULSE;
   
   // flush the buffers
   FlushCOM(portnum);

   // send the packet 
   if (WriteCOM(portnum,sendlen,sendpacket)) 
   {
      // read back the 2 byte response 
      if (ReadCOM(portnum,2,readbuffer) == 2)
      {
         // check response byte
         if (((readbuffer[0] | CMD_CONFIG) == 
                (CMD_CONFIG | PARMSEL_12VPULSE | PARMSET_512us)) &&
             ((readbuffer[1] & 0xFC) == 
                (0xFC & (CMD_COMM | FUNCTSEL_CHMOD | BITPOL_12V | SPEEDSEL_PULSE))))
            return TRUE;
      }
   }

   // an error occured so re-sync with DS2480
   DS2480Detect(portnum);

   return FALSE;
}