/*--------------------------------------------------------------------------- * 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.*; import com.dalsemi.onewire.container.OneWireContainer; /** * Memory bank class for the EPROM section of iButtons and 1-Wire devices. * * @version 0.00, 28 Aug 2000 * @author DS */ class MemoryBankAppReg implements OTPMemoryBank { //-------- //-------- Static Final Variables //-------- /** * Memory page size */ public static final int PAGE_SIZE = 8; /** * Read Memory Command */ public static final byte READ_MEMORY_COMMAND = ( byte ) 0xC3; /** * Main memory write command */ public static final byte WRITE_MEMORY_COMMAND = ( byte ) 0x99; /** * Copy/Lock command */ public static final byte COPY_LOCK_COMMAND = ( byte ) 0x5A; /** * Copy/Lock command */ public static final byte READ_STATUS_COMMAND = ( byte ) 0x66; /** * Copy/Lock validation key */ public static final byte VALIDATION_KEY = ( byte ) 0xA5; /** * Flag in status register indicated the page is locked */ public static final byte LOCKED_FLAG = ( byte ) 0xFC; //-------- //-------- 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; //-------- //-------- Protected Variables for MemoryBank implementation //-------- /** * Size of memory bank in bytes */ protected int size; /** * Memory bank descriptions */ protected static String bankDescription = "Application register, non-volatile when locked"; /** * Flag if read back verification is enabled in 'write()'. */ protected boolean writeVerification; //-------- //-------- Protected Variables for PagedMemoryBank implementation //-------- /** * Flag if reading a page in memory bank provides optional * extra information (counter, tamper protection, SHA-1...) */ protected boolean extraInfo; /** * Length of extra information when reading a page in memory bank */ protected int extraInfoLength; /** * Extra information descriptoin when reading page in memory bank */ protected static String extraInfoDescription = "Page Locked flag"; //-------- //-------- Protected Variables for OTPMemoryBank implementation //-------- //-------- //-------- Constructor //-------- /** * Memory bank contstuctor. Requires reference to the OneWireContainer * this memory bank resides on. Requires reference to memory banks used * in OTP operations. */ public MemoryBankAppReg (OneWireContainer ibutton) { // keep reference to ibutton where memory bank is ib = ibutton; // defaults writeVerification = true; // create the ffblock (used for faster 0xFF fills) ffBlock = new byte [50]; for (int i = 0; i < 50; i++) ffBlock [i] = ( byte ) 0xFF; } //-------- //-------- MemoryBank query 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 true; } /** * Query to see if current memory bank is read/write. * * @return 'true' if current memory bank is read/write */ public boolean isReadWrite () { return true; } /** * 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 false; } /** * Query to see if current memory bank is read only. * * @return 'true' if current memory bank can only be read */ public boolean isReadOnly () { return false; } /** * 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 false; } /** * 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 true; } /** * 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 0; } /** * Query to get the memory bank size in bytes. * * @return memory bank size in bytes. */ public int getSize () { return PAGE_SIZE; } //-------- //-------- PagedMemoryBank query methods //-------- /** * 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_SIZE; } /** * 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_SIZE - 2; } /** * 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 false; } /** * 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. */ public boolean haveExtraInfo () { 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 * 'haveExtraInfo()'. * * @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 'haveExtraInfo()'. * * @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 { byte result; // 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 'haveExtraInfo()' 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 'haveExtraInfo()' 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]; // check if current bank is not scratchpad bank, or not page 0 if (!this.extraInfo) throw new OneWireException( "Read extra information not supported on this memory bank"); // 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"); } /** * Read a Universal Data Packet and extra information. See the * method 'readPagePacket()' for a description of the packet structure. * See the method 'haveExtraInfo()' 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 * * @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) 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]); // return the length return raw_buf [0]; } else throw new OneWireIOException("Invalid CRC16 in packet read"); } /** * Write a Universal Data Packet. See the method 'readPagePacket()' * for a description of the packet structure. * * @param page page number to write packet to * @param writeBuf data byte array to write * @param offset offset into writeBuf where data to write is * @param len number of bytes to write * * @throws OneWireIOException * @throws OneWireException */ public void writePagePacket (int page, byte[] writeBuf, int offset, int len) throws OneWireIOException, OneWireException { // make sure length does not exceed max if (len > (PAGE_SIZE - 2)) throw new OneWireIOException( "Length of packet requested exceeds page size"); // construct the packet to write byte[] raw_buf = new byte [len + 3]; raw_buf [0] = ( byte ) len; System.arraycopy(writeBuf, 0, raw_buf, 1, len); int crc = CRC16.compute(raw_buf, 0, len + 1, page); raw_buf [len + 1] = ( byte ) (~crc & 0xFF); raw_buf [len + 2] = ( byte ) (((~crc & 0xFFFF) >>> 8) & 0xFF); // write the packet, return result write(page * PAGE_SIZE, raw_buf, 0, len + 3); } /** * Read a complete memory page with CRC verification provided by the * device. Not supported by all devices. See the method * 'hasPageAutoCRC()'. * * @param page page number to read * @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 * * @throws OneWireIOException * @throws OneWireException */ public void readPageCRC (int page, boolean readContinue, byte[] readBuf, int offset) throws OneWireIOException, OneWireException { // only needs to be implemented if supported by hardware throw new OneWireException( "Read page with CRC not supported by this memory bank"); } /** * Read a complete memory page with CRC verification provided by the * device with extra information. Not supported by all devices. * See the method 'hasPageAutoCRC()'. * See the method 'haveExtraInfo()' for a description of the optional * extra information. * * @param page page number to read * @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 * * @throws OneWireIOException * @throws OneWireException */ public void readPageCRC (int page, boolean readContinue, byte[] readBuf, int offset, byte[] extraInfo) throws OneWireIOException, OneWireException { // only needs to be implemented if supported by hardware throw new OneWireException( "Read page with CRC not supported by this memory bank"); } //-------- //-------- OTPMemoryBank I/O methods //-------- /** * Lock the specifed page in the current memory bank. Not supported * by all devices. See the method 'canLockPage()'. * * @param page number of page to lock * * @throws OneWireIOException * @throws OneWireException */ public void lockPage (int page) throws OneWireIOException, OneWireException { // 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"); // do the copy/lock sequence ib.adapter.putByte(COPY_LOCK_COMMAND); ib.adapter.putByte(VALIDATION_KEY); // read back to verify if (!isPageLocked(page)) throw new OneWireIOException( "Read back from write incorrect, could not lock page"); } /** * Query to see if the specified page is locked. * See the method 'canLockPage()'. * * @param page number of page to see if locked * * @return 'true' if page locked. * * @throws OneWireIOException * @throws OneWireException */ public boolean isPageLocked (int page) throws OneWireIOException, OneWireException { // check if for valid page if (page != 0) throw new OneWireException( "Invalid page number for this memory bank"); // attempt to put device at the correct speed ib.doSpeed(); // read status and return result return (( byte ) readStatus() == ( byte ) LOCKED_FLAG); } /** * Redirect the specifed page in the current memory bank to a new page. * Not supported by all devices. See the method 'canRedirectPage()'. * * @param page number of page to redirect * @param newPage new page number to redirect to * * @throws OneWireIOException * @throws OneWireException */ public void redirectPage (int page, int newPage) throws OneWireIOException, OneWireException { // only needs to be implemented if supported by hardware throw new OneWireException( "Page redirection not supported by this memory bank"); } /** * Query to see if the specified page is redirected. * Not supported by all devices. See the method 'canRedirectPage()'. * * @param page number of page check for redirection * * @return return the new page number or 0 if not redirected * * @throws OneWireIOException * @throws OneWireException */ public int isPageRedirected (int page) throws OneWireIOException, OneWireException { return 0; } /** * Lock the redirection option for the specifed page in the current * memory bank. Not supported by all devices. See the method * 'canLockRedirectPage()'. * * @param page number of page to redirect * * @throws OneWireIOException * @throws OneWireException */ public void lockRedirectPage (int page) throws OneWireIOException, OneWireException { // only needs to be implemented if supported by hardware throw new OneWireException( "Lock Page redirection not supported by this memory bank"); } /** * Query to see if the specified page has redirection locked. * Not supported by all devices. See the method 'canRedirectPage()'. * * @param page number of page check for locked redirection * * @return return 'true' if redirection is locked for this page * * @throws OneWireIOException * @throws OneWireException */ public boolean isRedirectPageLocked (int page) throws OneWireIOException, OneWireException { return false; } //-------- //-------- Bank specific methods //-------- /** * Read the status register for this memory bank. * * @param readBuf byte array to put data read. Must have at least * 'getExtraInfoLength()' elements. * @throws OneWireIOException * @throws OneWireException */ protected void readStatus (byte[] readBuf) throws OneWireIOException, OneWireException { readBuf [0] = ( byte ) readStatus(); } /** * Read the status register for this memory bank. * * @return the status register byte * * @throws OneWireIOException * @throws OneWireException */ protected byte readStatus () throws OneWireIOException, OneWireException { // select the device if (!ib.adapter.select(ib.address)) throw new OneWireIOException("Device select failed"); // do the read status sequence ib.adapter.putByte(READ_STATUS_COMMAND); // validation key ib.adapter.putByte(0); return ( byte ) ib.adapter.getByte(); } }