memorybankappreg.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

    * 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 true;
   }

   /**
    * 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 1;
   }

   /**
    * 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 extraInfoDescription;
   }

   /**
    * 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;
   }

   //--------
   //-------- OTPMemoryBank query methods
   //--------

   /**
    * Query to see if current memory bank pages can be redirected
    * to another pages.  This is mostly used in Write-Once memory
    * to provide a means to update.
    *
    * @return  'true' if current memory bank pages can be redirected
    *          to a new page.
    */
   public boolean canRedirectPage ()
   {
      return false;
   }

   /**
    * Query to see if current memory bank pages can be locked.  A
    * locked page would prevent any changes to the memory.
    *
    * @return  'true' if current memory bank pages can be redirected
    *          to a new page.
    */
   public boolean canLockPage ()
   {
      return true;
   }

   /**
    * Query to see if current memory bank pages can be locked from
    * being redirected.  This would prevent a Write-Once memory from
    * being updated.
    *
    * @return  'true' if current memory bank pages can be locked from
    *          being redirected to a new page.
    */
   public boolean canLockRedirectPage ()
   {
      return false;
   }

   //--------
   //-------- 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_SIZE)
         throw new OneWireException("Read exceeds memory bank end");

      // ignore readContinue, silly with a 8 byte memory bank
      // attempt to put device at the correct speed
      ib.doSpeed();

      // select the device
      if (!ib.adapter.select(ib.address))
         throw new OneWireIOException("Device select failed");

      // start the read
      ib.adapter.putByte(READ_MEMORY_COMMAND);
      ib.adapter.putByte(startAddr & 0xFF);

      // file the read block with 0xFF
      System.arraycopy(ffBlock, 0, readBuf, offset, len);

      // do the read
      ib.adapter.dataBlock(readBuf, offset, len);
   }

   /**
    * Write  memory in the current bank.  It is recommended that
    * when writing  data that some structure in the data is created
    * to provide error free reading back with read().  Or the
    * method 'writePagePacket()' could be used which automatically
    * wraps the data in a length and CRC.
    *
    * When using on Write-Once devices care must be taken to write into
    * into empty space.  If write() is used to write over an unlocked
    * page on a Write-Once device it will fail.  If write verification
    * is turned off with the method 'setWriteVerification(false)' then
    * the result will be an 'AND' of the existing data and the new data.
    *
    * @param  startAddr     starting address
    * @param  writeBuf      byte array containing data to write
    * @param  offset        offset into writeBuf to get data
    * @param  len           length in bytes to write
    *
    * @throws OneWireIOException
    * @throws OneWireException
    */
   public void write (int startAddr, byte[] writeBuf, int offset, int len)
      throws OneWireIOException, OneWireException
   {
      // return if nothing to do
      if (len == 0)
         return;

      // check if power delivery is available
      if (!ib.adapter.canDeliverPower())
         throw new OneWireException(
            "Power delivery required but not available");

      // check if write exceeds memory
      if ((startAddr + len) > PAGE_SIZE)
         throw new OneWireException("Write exceeds memory bank end");

      // attempt to put device at the correct speed
      ib.doSpeed();

      // select the device
      if (!ib.adapter.select(ib.address))
         throw new OneWireIOException("Device select failed");

      // start the write
      ib.adapter.putByte(WRITE_MEMORY_COMMAND);
      ib.adapter.putByte(startAddr & 0xFF);

      // do the write
      ib.adapter.dataBlock(writeBuf, offset, len);

      // check for write verification
      if (writeVerification)
      {

         // read back
         byte[] read_buf = new byte [len];

         read(startAddr, true, read_buf, 0, len);

         // compare
         for (int i = 0; i < len; i++)
         {
            if (( byte ) read_buf [i] != ( byte ) writeBuf [i + offset])
               throw new OneWireIOException(
                  "Read back from write compare is incorrect, page may be locked");
         }
      }
   }

   //--------
   //-------- PagedMemoryBank I/O methods
   //--------

   /**
    * Read  page 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  page          page number to read packet from
    * @param  readContinue  if 'true' then device read is continued without
    *                       re-selecting.  This can only be used if the new
    *                       readPage() 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
    *
    * @throws OneWireIOException
    * @throws OneWireException
    */
   public void readPage (int page, boolean readContinue, byte[] readBuf,
                         int offset)
      throws OneWireIOException, OneWireException
   {

      // check if for valid page
      if (page != 0)
         throw new OneWireException(
            "Invalid page number for this memory bank");

      // do the read
      read(0, true, readBuf, offset, PAGE_SIZE);
   }

   /**
    * Read  page with extra information 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.
    * See the method 'hasExtraInfo()' for a description of the optional
    * extra information some devices have.
    *
    * @param  page          page number to read packet from
    * @param  readContinue  if 'true' then device read is continued without
    *                       re-selecting.  This can only be used if the new
    *                       readPage() 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  extraInfo     byte array to put extra info read into
    *
    * @throws OneWireIOException
    * @throws OneWireException
    */
   public void readPage (int page, boolean readContinue, byte[] readBuf,
                         int offset, byte[] extraInfo)
      throws OneWireIOException, OneWireException
   {

      // read the page data
      read(page, true, readBuf, offset, PAGE_SIZE);

      // read the extra information (status)
      readStatus(extraInfo);
   }

   /**
    * Read a Universal Data Packet and extra information.  See the
    * method 'readPagePacket()' for a description of the packet structure.
    * See the method 'hasExtraInfo()' for a description of the optional
    * extra information some devices have.
    *
    * @param  page          page number to read packet from
    * @param  readContinue  if 'true' then device read is continued without
    *                       re-selecting.  This can only be used if the new
    *                       readPagePacket() continious where the last one
    *                       stopped and it is inside a
    *                       'beginExclusive/endExclusive' block.
    * @param  readBuf       byte array to put data read. Must have at least
    *                       'getMaxPacketDataLength()' elements.
    * @param  offset        offset into readBuf to place data
    * @param  extraInfo     byte array to put extra info read into
    *
    * @return  number of data bytes written to readBuf at the offset.
    *
    * @throws OneWireIOException
    * @throws OneWireException
    */
   public int readPagePacket (int page, boolean readContinue, byte[] readBuf,
                              int offset, byte[] extraInfo)
      throws OneWireIOException, OneWireException
   {
      byte[] raw_buf = new byte [PAGE_SIZE];

      // read the entire page data
      read(page, true, raw_buf, 0, PAGE_SIZE);

      // check if length is realistic
      if (raw_buf [0] > (PAGE_SIZE - 2))
         throw new OneWireIOException("Invalid length in packet");

      // verify the CRC is correct
      if (CRC16.compute(raw_buf, 0, raw_buf [0] + 3, page) == 0x0000B001)
      {

         // extract the data out of the packet
         System.arraycopy(raw_buf, 1, readBuf, offset, raw_buf [0]);

         // read the extra info
         readStatus(extraInfo);

         // return the length
         return raw_buf [0];
      }
      else
         throw new OneWireIOException("Invalid CRC16 in packet read");