memorybankad.java

这是一个以JAVA编写的程序,本人还没有试过,是一个简单的温度控制系统

/*---------------------------------------------------------------------------
 * Copyright (C) 1999,2000 Dallas Semiconductor Corporation, All Rights Reserved.
 *
 * 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 DALLAS SEMICONDUCTOR 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.
 *
 * Except as contained in this notice, the name of Dallas Semiconductor
 * shall not be used except as stated in the Dallas Semiconductor
 * Branding Policy.
 *---------------------------------------------------------------------------
 */

package com.dalsemi.onewire.container;

// imports
import com.dalsemi.onewire.OneWireException;
import com.dalsemi.onewire.adapter.*;
import com.dalsemi.onewire.utils.CRC16;
import com.dalsemi.onewire.container.OneWireContainer;


/**
 * Memory bank class for the DS2450.
 *
 *  @version    0.00, 28 Aug 2000
 *  @author     DS
 */
class MemoryBankAD
   implements PagedMemoryBank
{

   //--------
   //--------Static Final Variables
   //--------

   /**
     * Read Memory Command
     */
   public static final byte READ_MEMORY_COMMAND = ( byte ) 0xAA;

   /**
     * Write Memory Command
     */
   public static final byte WRITE_MEMORY_COMMAND = ( byte ) 0x55;

   /**
     * Page length
     */
   public static final int PAGE_LENGTH = 8;

   //--------
   //-------- Variables
   //--------

   /**
    * Reference to the OneWireContainer this bank resides on.
    */
   protected OneWireContainer ib;

   /**
    * block of 0xFF's used for faster read pre-fill of 1-Wire blocks
    */
   protected byte[] ffBlock;

   /**
    * Flag if read back verification is enabled in 'write()'.
    */
   protected boolean writeVerification;

   /**
    * Flag to indicate that speed needs to be set
    */
   protected boolean doSetSpeed;

   //--------
   //-------- Protected Variables for MemoryBank implementation 
   //--------

   /**
    * Memory bank descriptions
    */
   protected String bankDescription;

   /**
    * Memory bank usage flags
    */
   protected boolean generalPurposeMemory;

   /**
    * Flag if memory bank is read/write
    */
   protected boolean readWrite;

   /**
    * Flag if memory bank is write once (EPROM)
    */
   protected boolean writeOnce;

   /**
    * Flag if memory bank is read only
    */
   protected boolean readOnly;

   /**
    * Flag if memory bank is non volatile
    * (will not erase when power removed)
    */
   protected boolean nonVolatile;

   /**
    * Starting physical address in memory bank.  Needed for different
    * types of memory in the same logical memory bank.  This can be
    * used to seperate them into two virtual memory banks.  Example:
    * DS2406 status page has mixed EPROM and Volatile RAM.
    */
   protected int startPhysicalAddress;

   //--------
   //-------- Constructor
   //--------

   /**
    * Memory bank contstuctor.  Requires reference to the OneWireContainer
    * this memory bank resides on.
    */
   public MemoryBankAD (OneWireContainer ibutton)
   {

      // keep reference to ibutton where memory bank is
      ib = ibutton;

      // create the ffblock (used for faster 0xFF fills)
      ffBlock = new byte [50];

      for (int i = 0; i < 50; i++)
         ffBlock [i] = ( byte ) 0xFF;

      // defaults for Page0 of DS2450
      bankDescription      = "A/D Conversion read-out";
      generalPurposeMemory = false;
      startPhysicalAddress = 0;
      readWrite            = false;
      writeOnce            = false;
      readOnly             = true;
      nonVolatile          = false;
      writeVerification    = true;

      // indicate speed has not been set
      doSetSpeed = true;
   }

   //--------
   //-------- Memory Bank methods
   //--------

   /**
    * Query to see get a string description of the current memory bank.
    *
    * @return  String containing the memory bank description
    */
   public String getBankDescription ()
   {
      return bankDescription;
   }

   /**
    * Query to see if the current memory bank is general purpose
    * user memory.  If it is NOT then it is Memory-Mapped and writing
    * values to this memory will affect the behavior of the 1-Wire
    * device.
    *
    * @return  'true' if current memory bank is general purpose
    */
   public boolean isGeneralPurposeMemory ()
   {
      return generalPurposeMemory;
   }

   /**
    * Query to see if current memory bank is read/write.
    *
    * @return  'true' if current memory bank is read/write
    */
   public boolean isReadWrite ()
   {
      return readWrite;
   }

   /**
    * Query to see if current memory bank is write write once such
    * as with EPROM technology.
    *
    * @return  'true' if current memory bank can only be written once
    */
   public boolean isWriteOnce ()
   {
      return writeOnce;
   }

   /**
    * Query to see if current memory bank is read only.
    *
    * @return  'true' if current memory bank can only be read
    */
   public boolean isReadOnly ()
   {
      return readOnly;
   }

   /**
    * Query to see if current memory bank non-volatile.  Memory is
    * non-volatile if it retains its contents even when removed from
    * the 1-Wire network.
    *
    * @return  'true' if current memory bank non volatile.
    */
   public boolean isNonVolatile ()
   {
      return nonVolatile;
   }

   /**
    * Query to see if current memory bank pages need the adapter to
    * have a 'ProgramPulse' in order to write to the memory.
    *
    * @return  'true' if writing to the current memory bank pages
    *                 requires a 'ProgramPulse'.
    */
   public boolean needsProgramPulse ()
   {
      return false;
   }

   /**
    * Query to see if current memory bank pages need the adapter to
    * have a 'PowerDelivery' feature in order to write to the memory.
    *
    * @return  'true' if writing to the current memory bank pages
    *                 requires 'PowerDelivery'.
    */
   public boolean needsPowerDelivery ()
   {
      return false;
   }

   /**
    * Query to get the starting physical address of this bank.  Physical
    * banks are sometimes sub-divided into logical banks due to changes
    * in attributes.
    *
    * @return  physical starting address of this logical bank.
    */
   public int getStartPhysicalAddress ()
   {
      return startPhysicalAddress;
   }

   /**
    * Query to get the memory bank size in bytes.
    *
    * @return  memory bank size in bytes.
    */
   public int getSize ()
   {
      return PAGE_LENGTH;
   }

   /**
    * Set the write verification for the 'write()' method.
    *
    * @param  doReadVerf   true (default) verify write in 'write'
    *                      false, don't verify write (used on
    *                      Write-Once bit manipulation)
    */
   public void setWriteVerification (boolean doReadVerf)
   {
      writeVerification = doReadVerf;
   }

   /**
    * Query to get the number of pages in current memory bank.
    *
    * @return  number of pages in current memory bank
    */
   public int getNumberPages ()
   {
      return 1;
   }

   /**
    * Query to get  page length in bytes in current memory bank.
    *
    * @return   page length in bytes in current memory bank
    */
   public int getPageLength ()
   {
      return PAGE_LENGTH;
   }

   /**
    * Query to get Maximum data page length in bytes for a packet
    * read or written in the current memory bank.  See the 'ReadPagePacket()'
    * and 'WritePagePacket()' methods.  This method is only usefull
    * if the current memory bank is general purpose memory.
    *
    * @return  max packet page length in bytes in current memory bank
    */
   public int getMaxPacketDataLength ()
   {
      return PAGE_LENGTH - 3;
   }

   /**
    * Query to see if current memory bank pages can be read with
    * the contents being verified by a device generated CRC.
    * This is used to see if the 'ReadPageCRC()' can be used.
    *
    * @return  'true' if current memory bank can be read with self
    *          generated CRC.
    */
   public boolean hasPageAutoCRC ()
   {
      return true;
   }

   /**
    * Query to see if current memory bank pages when read deliver
    * extra information outside of the normal data space.  Examples
    * of this may be a redirection byte, counter, tamper protection
    * bytes, or SHA-1 result.  If this method returns true then the
    * methods 'ReadPagePacket()' and 'readPageCRC()' with 'extraInfo'
    * parameter can be used.
    *
    * @return  'true' if reading the current memory bank pages
    *                 provides extra information.
    *
    * @deprecated  As of 1-Wire API 0.01, replaced by {@link #hasExtraInfo()}
    */
   public boolean haveExtraInfo ()
   {
      return false;
   }

   /**
    * Checks to see if this memory bank's pages deliver extra 
    * information outside of the normal data space,  when read.  Examples
    * of this may be a redirection byte, counter, tamper protection
    * bytes, or SHA-1 result.  If this method returns true then the
    * methods with an 'extraInfo' parameter can be used:
    * {@link #readPage(int,boolean,byte[],int,byte[]) readPage},
    * {@link #readPageCRC(int,boolean,byte[],int,byte[]) readPageCRC}, and
    * {@link #readPagePacket(int,boolean,byte[],int,byte[]) readPagePacket}.
    *
    * @return  <CODE> true </CODE> if reading the this memory bank's 
    *                 pages provides extra information
    *
    * @see #readPage(int,boolean,byte[],int,byte[]) readPage(extra)
    * @see #readPageCRC(int,boolean,byte[],int,byte[]) readPageCRC(extra)
    * @see #readPagePacket(int,boolean,byte[],int,byte[]) readPagePacket(extra)
    * @since 1-Wire API 0.01
    */
   public boolean hasExtraInfo ()
   {
      return false;
   }

   /**
    * Query to get the length in bytes of extra information that
    * is read when read a page in the current memory bank.  See
    * 'hasExtraInfo()'.
    *
    * @return  number of bytes in Extra Information read when reading
    *          pages in the current memory bank.
    */
   public int getExtraInfoLength ()
   {
      return 0;
   }

   /**
    * Query to get a string description of what is contained in
    * the Extra Informationed return when reading pages in the current
    * memory bank.  See 'hasExtraInfo()'.
    *
    * @return string describing extra information.
    */
   public String getExtraInfoDescription ()
   {
      return null;
   }

   //--------
   //-------- MemoryBank I/O methods
   //--------

   /**
    * Read  memory in the current bank with no CRC checking (device or
    * data). The resulting data from this API may or may not be what is on
    * the 1-Wire device.  It is recommends that the data contain some kind
    * of checking (CRC) like in the readPagePacket() method or have
    * the 1-Wire device provide the CRC as in readPageCRC().  readPageCRC()
    * however is not supported on all memory types, see 'hasPageAutoCRC()'.
    * If neither is an option then this method could be called more
    * then once to at least verify that the same thing is read consistantly.
    *
    * @param  startAddr     starting physical address
    * @param  readContinue  if 'true' then device read is continued without
    *                       re-selecting.  This can only be used if the new
    *                       read() continious where the last one led off
    *                       and it is inside a 'beginExclusive/endExclusive'
    *                       block.
    * @param  readBuf       byte array to place read data into
    * @param  offset        offset into readBuf to place data
    * @param  len           length in bytes to read
    *
    * @throws OneWireIOException
    * @throws OneWireException
    */
   public void read (int startAddr, boolean readContinue, byte[] readBuf,
                     int offset, int len)
      throws OneWireIOException, OneWireException
   {

      // check if read exceeds memory
      if ((startAddr + len) > PAGE_LENGTH)
         throw new OneWireException("Read exceeds memory bank end");

      // no regular read memory so must use readPageCRC
      int start_pg = startAddr / PAGE_LENGTH;
      int end_pg   = ((startAddr + len) / PAGE_LENGTH) - 1;

      if (((startAddr + len) % PAGE_LENGTH) > 0)
         end_pg++;

      byte[] raw_buf = new byte [(end_pg - start_pg + 1) * PAGE_LENGTH];