//---------------------------------------------------------------------------
// Copyright (C) 2000 Dallas Semiconductor Corporation, All Rights Reserved.
// 
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// copy of this software and associated documentation files (the "Software"), 
// to deal in the Software without restriction, including without limitation 
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// 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.
// 
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// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 
// MERCHANTABILITY,  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 
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// OTHER DEALINGS IN THE SOFTWARE.
// 
// Except as contained in this notice, the name of Dallas Semiconductor 
// shall not be used except as stated in the Dallas Semiconductor 
// Branding Policy. 
//---------------------------------------------------------------------------
// 
// mbSCREE.c - Memory bank class for the Scratchpad section of EEPROM iButtons and
//             1-Wire devices.
//
// Version: 2.10
//

// Include Files
#include "mbscree.h"

// general command defines 
#define WRITE_SCRATCHPAD_COMMAND 0x0F
#define COPY_SCRATCHPAD_COMMAND 0x55

// Local defines
#define SIZE_SCRATCH_EE 32
#define PAGE_LENGTH_SCRATCH_EE 32

// External functions
extern SMALLINT owBlock(int,int,uchar *,int);
extern SMALLINT owAccess(int);
extern void     setcrc16(int,ushort);
extern ushort   docrc16(int,ushort);
extern SMALLINT owWriteBytePower(int,int);
extern void     msDelay(int);
extern SMALLINT owLevel(int,int);
extern SMALLINT owReadByte(int);


/**
 * Write to the scratchpad page of memory a 23 family device.
 *
 * @param  startAddr     starting address
 * @param  writeBuf      byte array containing data to write
 * @param  offset        offset into readBuf to place data
 * @param  len           length in bytes to write
 *
 * @return 'true' if writing was successful
 */
SMALLINT writeScratchPadEE(int portnum,int str_add, uchar *writeBuf, int len)
{
   uchar raw_buf[PAGE_LENGTH_SCRATCH_EE+5];
   int send_len = 0;
   int i;
   ushort lastcrc16;

   // select the device
   if (!owAccess(portnum))
   {
      OWERROR(OWERROR_DEVICE_SELECT_FAIL);
      return FALSE;
   }

   // build block to send
   raw_buf[0] = WRITE_SCRATCHPAD_COMMAND;
   raw_buf[1] = str_add & 0xFF;
   raw_buf[2] = ((str_add & 0xFFFF) >> 8) & 0xFF;

   for(i=3;i<len+3;i++)
      raw_buf[i] = writeBuf[i-3];

   // check if full page (can utilize CRC)
   if (((str_add + len) % PAGE_LENGTH_SCRATCH_EE) == 0)
   {
      for(i=len+3;i<len+5;i++)
         raw_buf[i] = 0xFF;

      send_len = PAGE_LENGTH_SCRATCH_EE + 5;
   }
   else
      send_len = len + 3;

   // send block, return result 
   if(!owBlock(portnum,FALSE,raw_buf,send_len))
   {
      OWERROR(OWERROR_BLOCK_FAILED);
      return FALSE;
   }

   if(send_len == (PAGE_LENGTH_SCRATCH_EE+5))
   {
      // verify the CRC is correct
      setcrc16(portnum,0);
      for(i=0;i<(raw_buf[0]+3);i++)
         lastcrc16 = docrc16(portnum,raw_buf[i]);

      if(lastcrc16 == 0xB001)
      {
         OWERROR(OWERROR_CRC_FAILED);
         return FALSE;
      }
   }

   return TRUE;
}


/**
 * Copy the scratchpad page to memory of a 23h device.
 *
 * portnum       the port number of the port being used for the
 *               1-Wire Network.
 * str_add       starting address
 * len           length in bytes that was written already
 *
 * @return       'true' if the coping was successful.
 */
SMALLINT copyScratchPadEE(int portnum, int str_add, int len)
{
   uchar raw_buf[3];
   SMALLINT rslt = 0;

   // select the device
   if (!owAccess(portnum))
   {
      OWERROR(OWERROR_DEVICE_SELECT_FAIL);
      return FALSE;
   }

   // build block to send
   raw_buf[0] = COPY_SCRATCHPAD_COMMAND;
   raw_buf[1] = str_add & 0xFF;
   raw_buf[2] = ((str_add & 0xFFFF) >> 8) & 0xFF;

   // send block (check copy indication complete)
   if(!owBlock(portnum,FALSE,raw_buf,3))
   {
      OWERROR(OWERROR_BLOCK_FAILED);
      return FALSE;
   }

   if(!owWriteBytePower(portnum,((str_add + len - 1) & 0x1F)))
      return FALSE;

   msDelay(5);

   rslt = owLevel(portnum,MODE_NORMAL);

   if(MODE_NORMAL != rslt)
      return FALSE;

   rslt = owReadByte(portnum);

   if (((uchar) (rslt & 0x0F0) != (uchar) 0xA0)
              && ((uchar) (rslt & 0x0F0) != (uchar) 0x50))
   {
      OWERROR(OWERROR_COPY_SCRATCHPAD_NOT_FOUND);
      return FALSE;      
   }

   return TRUE;
}