/*--------------------------------------------------------------------------- * 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. */ public boolean haveExtraInfo () { 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 * 'haveExtraInfo()'. * * @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 'haveExtraInfo()'. * * @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]; // loop to read the pages for (int pg = start_pg; pg <= end_pg; pg++) readPageCRC(pg, !(pg == start_pg), raw_buf, (pg - start_pg) * PAGE_LENGTH); // extract out the data System.arraycopy(raw_buf, (startAddr % PAGE_LENGTH), 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[] raw_buf = new byte [7]; int i, cnt = 0, start_addr, addr, end_addr, lastcrc; // return if nothing to do if (len == 0) return; // attempt to put device at max desired speed checkSpeed(); // select the device if (!ib.adapter.select(ib.address)) { forceVerify(); throw new OneWireIOException("Device select failed"); } // build packet raw_buf [cnt++] = WRITE_MEMORY_COMMAND; start_addr = startAddr + startPhysicalAddress; end_addr = start_addr + len; raw_buf [cnt++] = ( byte ) (start_addr & 0xFF); raw_buf [cnt++] = ( byte ) (((start_addr & 0xFFFF) >>> 8) & 0xFF); // loop for each byte to write for (addr = start_addr; addr < end_addr; addr++) { // add the byte to write to buffer raw_buf [cnt++] = writeBuf [offset + addr - start_addr]; // initialize crc16 lastcrc = CRC16.compute(raw_buf, 0, cnt, (addr == start_addr) ? 0 : addr); // add the read crc and echo byte to block System.arraycopy(ffBlock, 0, raw_buf, cnt, 3); // perform the block ib.adapter.dataBlock(raw_buf, 0, cnt + 3); // check the CRC if (CRC16.compute(raw_buf, cnt, 2, lastcrc) != 0x0000B001) { forceVerify(); throw new OneWireIOException("Invalid CRC16 read from device"); } // check echo if (raw_buf [cnt + 2] != writeBuf [offset + addr - start_addr]) { forceVerify(); throw new OneWireIOException("Write byte echo was invalid"); } // reset the buffer and loop cnt = 0; } } //-------- //-------- 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 { // read page with read page CRC readPageCRC(page, readContinue, readBuf, offset); } /** * 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 { // only needs to be implemented if supported by hardware throw new OneWireException( "Read page with extra-info not supported by this memory bank"); } /** * Read a Universal Data Packet. * * The Universal Data Packet always starts on page boundaries but * can end anywhere in the page. The structure specifies the length of * data bytes not including the length byte and the CRC16 bytes. * There is one length byte. The CRC16 is first initialized to * the page number. This provides a check to verify the page that * was intended is being read. The CRC16 is then calculated over * the length and data bytes. The CRC16 is then inverted and stored * low byte first followed by the high byte. This is structure is * used by this method to verify the data but is not returned, only * the data payload is returned. * * @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 read from the device and 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_LENGTH]; // read entire page with read page CRC readPageCRC(page, readContinue, raw_buf, 0); // check if length is realistic if (raw_buf [0] > (PAGE_LENGTH - 3)) 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 { forceVerify(); 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 * @param extraInfo byte array to put extra info read into * * @return number of data bytes read from the device and 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 { // only needs to be implemented if supported by hardware throw new OneWireException( "Read page packet with extra-info not supported by this memory bank"); } /** * 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_LENGTH - 3) 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_LENGTH, 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 { byte[] raw_buf = new byte [5 + PAGE_LENGTH]; int len; // attempt to put device at max desired speed if (!readContinue) checkSpeed(); // see if need to access the device if (!readContinue) { // select the device if (!ib.adapter.select(ib.address)) { forceVerify(); throw new OneWireIOException("Device select failed"); } // build start reading memory block with: command, address len = raw_buf.length; System.arraycopy(ffBlock, 0, raw_buf, 0, len); raw_buf [0] = READ_MEMORY_COMMAND; int addr = page * PAGE_LENGTH + startPhysicalAddress; raw_buf [1] = ( byte ) (addr & 0xFF); raw_buf [2] = ( byte ) (((addr & 0xFFFF) >>> 8) & 0xFF); } else { len = PAGE_LENGTH + 2; System.arraycopy(ffBlock, 0, raw_buf, 0, len); } // do the block ib.adapter.dataBlock(raw_buf, 0, len); // check the CRC if (CRC16.compute(raw_buf, 0, len, 0) != 0x0000B001) { forceVerify(); throw new OneWireIOException("Invalid CRC16 read from device"); } // extract the data to return System.arraycopy(raw_buf, len - 2 - PAGE_LENGTH, readBuf, offset, PAGE_LENGTH); } /** * 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 and extra-info not supported by this memory bank"); } //-------- //-------- checkSpeed methods //-------- /** * Check the device speed if has not been done before or if * an error was detected. * * @throws OneWireIOException * @throws OneWireException */ public void checkSpeed () throws OneWireIOException, OneWireException { synchronized (this) { // only check the speed if (doSetSpeed) { // attempt to set the correct speed and verify device present ib.doSpeed(); // no execptions so clear flag doSetSpeed = false; } } } /** * Set the flag to indicate the next 'checkSpeed()' will force * a speed set and verify 'doSpeed()'. */ public void forceVerify () { synchronized (this) { doSetSpeed = true; } } }