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/** * Copyright (c) 2010-2017 by the respective copyright holders. * * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/epl-v10.html */ package de.csdev.ebus.utils; import java.nio.ByteBuffer; import javax.xml.bind.DatatypeConverter; import org.apache.commons.lang.StringUtils; import de.csdev.ebus.core.EBusConsts; /** * A helper class to decode all eBus data types and telegrams. * * @author Christian Sowada - Initial contribution * */ public class EBusUtils { /** calculated crc values */ final static public byte CRC_TAB_8_VALUE[] = { (byte) 0x00, (byte) 0x9B, (byte) 0xAD, (byte) 0x36, (byte) 0xC1, (byte) 0x5A, (byte) 0x6C, (byte) 0xF7, (byte) 0x19, (byte) 0x82, (byte) 0xB4, (byte) 0x2F, (byte) 0xD8, (byte) 0x43, (byte) 0x75, (byte) 0xEE, (byte) 0x32, (byte) 0xA9, (byte) 0x9F, (byte) 0x04, (byte) 0xF3, (byte) 0x68, (byte) 0x5E, (byte) 0xC5, (byte) 0x2B, (byte) 0xB0, (byte) 0x86, (byte) 0x1D, (byte) 0xEA, (byte) 0x71, (byte) 0x47, (byte) 0xDC, (byte) 0x64, (byte) 0xFF, (byte) 0xC9, (byte) 0x52, (byte) 0xA5, (byte) 0x3E, (byte) 0x08, (byte) 0x93, (byte) 0x7D, (byte) 0xE6, (byte) 0xD0, (byte) 0x4B, (byte) 0xBC, (byte) 0x27, (byte) 0x11, (byte) 0x8A, (byte) 0x56, (byte) 0xCD, (byte) 0xFB, (byte) 0x60, (byte) 0x97, (byte) 0x0C, (byte) 0x3A, (byte) 0xA1, (byte) 0x4F, (byte) 0xD4, (byte) 0xE2, (byte) 0x79, (byte) 0x8E, (byte) 0x15, (byte) 0x23, (byte) 0xB8, (byte) 0xC8, (byte) 0x53, (byte) 0x65, (byte) 0xFE, (byte) 0x09, (byte) 0x92, (byte) 0xA4, (byte) 0x3F, (byte) 0xD1, (byte) 0x4A, (byte) 0x7C, (byte) 0xE7, (byte) 0x10, (byte) 0x8B, (byte) 0xBD, (byte) 0x26, (byte) 0xFA, (byte) 0x61, (byte) 0x57, (byte) 0xCC, (byte) 0x3B, (byte) 0xA0, (byte) 0x96, (byte) 0x0D, (byte) 0xE3, (byte) 0x78, (byte) 0x4E, (byte) 0xD5, (byte) 0x22, (byte) 0xB9, (byte) 0x8F, (byte) 0x14, (byte) 0xAC, (byte) 0x37, (byte) 0x01, (byte) 0x9A, (byte) 0x6D, (byte) 0xF6, (byte) 0xC0, (byte) 0x5B, (byte) 0xB5, (byte) 0x2E, (byte) 0x18, (byte) 0x83, (byte) 0x74, (byte) 0xEF, (byte) 0xD9, (byte) 0x42, (byte) 0x9E, (byte) 0x05, (byte) 0x33, (byte) 0xA8, (byte) 0x5F, (byte) 0xC4, (byte) 0xF2, (byte) 0x69, (byte) 0x87, (byte) 0x1C, (byte) 0x2A, (byte) 0xB1, (byte) 0x46, (byte) 0xDD, (byte) 0xEB, (byte) 0x70, (byte) 0x0B, (byte) 0x90, (byte) 0xA6, (byte) 0x3D, (byte) 0xCA, (byte) 0x51, (byte) 0x67, (byte) 0xFC, (byte) 0x12, (byte) 0x89, (byte) 0xBF, (byte) 0x24, (byte) 0xD3, (byte) 0x48, (byte) 0x7E, (byte) 0xE5, (byte) 0x39, (byte) 0xA2, (byte) 0x94, (byte) 0x0F, (byte) 0xF8, (byte) 0x63, (byte) 0x55, (byte) 0xCE, (byte) 0x20, (byte) 0xBB, (byte) 0x8D, (byte) 0x16, (byte) 0xE1, (byte) 0x7A, (byte) 0x4C, (byte) 0xD7, (byte) 0x6F, (byte) 0xF4, (byte) 0xC2, (byte) 0x59, (byte) 0xAE, (byte) 0x35, (byte) 0x03, (byte) 0x98, (byte) 0x76, (byte) 0xED, (byte) 0xDB, (byte) 0x40, (byte) 0xB7, (byte) 0x2C, (byte) 0x1A, (byte) 0x81, (byte) 0x5D, (byte) 0xC6, (byte) 0xF0, (byte) 0x6B, (byte) 0x9C, (byte) 0x07, (byte) 0x31, (byte) 0xAA, (byte) 0x44, (byte) 0xDF, (byte) 0xE9, (byte) 0x72, (byte) 0x85, (byte) 0x1E, (byte) 0x28, (byte) 0xB3, (byte) 0xC3, (byte) 0x58, (byte) 0x6E, (byte) 0xF5, (byte) 0x02, (byte) 0x99, (byte) 0xAF, (byte) 0x34, (byte) 0xDA, (byte) 0x41, (byte) 0x77, (byte) 0xEC, (byte) 0x1B, (byte) 0x80, (byte) 0xB6, (byte) 0x2D, (byte) 0xF1, (byte) 0x6A, (byte) 0x5C, (byte) 0xC7, (byte) 0x30, (byte) 0xAB, (byte) 0x9D, (byte) 0x06, (byte) 0xE8, (byte) 0x73, (byte) 0x45, (byte) 0xDE, (byte) 0x29, (byte) 0xB2, (byte) 0x84, (byte) 0x1F, (byte) 0xA7, (byte) 0x3C, (byte) 0x0A, (byte) 0x91, (byte) 0x66, (byte) 0xFD, (byte) 0xCB, (byte) 0x50, (byte) 0xBE, (byte) 0x25, (byte) 0x13, (byte) 0x88, (byte) 0x7F, (byte) 0xE4, (byte) 0xD2, (byte) 0x49, (byte) 0x95, (byte) 0x0E, (byte) 0x38, (byte) 0xA3, (byte) 0x54, (byte) 0xCF, (byte) 0xF9, (byte) 0x62, (byte) 0x8C, (byte) 0x17, (byte) 0x21, (byte) 0xBA, (byte) 0x4D, (byte) 0xD6, (byte) 0xE0, (byte) 0x7B }; /** * Left pad byte array to a byte array with given size. * * @param source Source array * @param size The final byte array size * @return The new byte arrray or <code>null</code> if the source array is to large */ public static byte[] leftPadByteArray(byte[] source, int size) { byte[] bs = new byte[size]; if (size < source.length) { return null; } int startPos = size - source.length; System.arraycopy(source, 0, bs, startPos, source.length); return bs; } /** * CRC calculation * * @param data The byte to crc check * @param crcInit The current crc result or another start value * @param poly The polynom * @return The crc result */ public static byte crc8(byte data, byte crcInit, byte poly) { byte crc; byte polynom; int i; crc = crcInit; for (i = 0; i < 8; i++) { if ((uint(crc) & 0x80) != 0) { polynom = poly; } else { polynom = (byte) 0; } crc = (byte) ((uint(crc) & ~0x80) << 1); if ((uint(data) & 0x80) != 0) { crc = (byte) (uint(crc) | 1); } crc = (byte) (uint(crc) ^ uint(polynom)); data = (byte) (uint(data) << 1); } return crc; } /** * @param data * @param len * @return */ public static byte crc8(byte[] data, int len) { byte uc_crc = 0; for (int i = 0; i < len; i++) { byte b = data[i]; uc_crc = crc8_tab(b, uc_crc); } return uc_crc; } /** * CRC calculation with tab operations * * @param data The byte to crc check * @param crcInit The current crc result or another start value * @return The crc result */ public static byte crc8_tab(byte data, byte crcInit) { short ci = (short) (crcInit & 0xFF); byte crc = (byte) (CRC_TAB_8_VALUE[ci] ^ (data & 0xFF)); return crc; } /** * Returns the master address based on a slave address if possible. Not all slave address have a valid master * address. * * @param slaveAddress * @return */ static public Byte getMasterAddress(byte slaveAddress) { if (!isMasterAddress(slaveAddress)) { byte masterAddress = (byte) (slaveAddress == (byte) 0x04 ? (byte) 0xFF : slaveAddress - 5); if (isMasterAddress(masterAddress)) { return masterAddress; } } return null; } /** * Compute the slave address based on the master address. * * @param masterAddress The master address * @return The slave address or null if the master address is invalid */ static public Byte getSlaveAddress(byte masterAddress) { if (isMasterAddress(masterAddress)) { return (byte) (masterAddress == (byte) 0xFF ? (byte) 0x04 : masterAddress + 5); } return null; } /** * Check if the address is a valid master address. * * @param address * @return */ public static boolean isMasterAddress(byte address) { byte addr = (byte) ((byte) (address >>> 4) & (byte) 0x0F); byte prio = (byte) (address & (byte) 0x0F); if (isValidAddress(address)) { if (addr == (byte) 0x00 || addr == (byte) 0x01 || addr == (byte) 0x03 || addr == (byte) 0x07 || addr == (byte) 0x0F) { if (prio == (byte) 0x00 || prio == (byte) 0x01 || prio == (byte) 0x03 || prio == (byte) 0x07 || prio == (byte) 0x0F) { return true; } } } return false; } /** * Check if the address is in general valid * * @param address * @return */ public static boolean isValidAddress(byte address) { if (address == EBusConsts.BROADCAST_ADDRESS || address == EBusConsts.SYN || address == EBusConsts.ESCAPE) { return false; } return true; } /** * FIXME: Badly programmed * * @param hexDumpString * @return */ static public Byte toByte(String hexDumpString) { if (StringUtils.isEmpty(hexDumpString)) { return null; } return toByteArray(hexDumpString)[0]; } /** * Convert a ByteBuffer to a byte array * * @param buffer * @return */ public static byte[] toByteArray(ByteBuffer buffer) { int size = 0; if (buffer.position() == 0) { size = buffer.limit(); } else { size = buffer.position(); } byte[] data = new byte[size]; ((ByteBuffer) buffer.duplicate().clear()).get(data); return data; } /** * Converts a hex string to byte array * * @param hexDumpString * @return */ static public byte[] toByteArray(String hexDumpString) { if (StringUtils.isEmpty(hexDumpString)) { return new byte[0]; } return DatatypeConverter.parseHexBinary(hexDumpString.replaceAll(" ", "")); } /** * Generates a hex string representative of byte data * * @param data The source * @return The hex string */ static public String toHexDumpString(Byte data) { if (data == null) { return ""; } return String.format("%02X", (0xFF & data)); } /** * Generates a string hex dump from a byte array * * @param data The source * @return The StringBuilder with hex dump */ static public StringBuilder toHexDumpString(byte[] data) { StringBuilder sb = new StringBuilder(); if (data != null && data.length > 0) { for (int i = 0; i < data.length; i++) { byte c = data[i]; if (i > 0) { sb.append(' '); } sb.append(toHexDumpString(c)); } } return sb; } /** * Generates a string hex dump from a ByteBuffer * * @param data The source * @return The StringBuilder with hex dump */ static public StringBuilder toHexDumpString(ByteBuffer data) { int size = 0; if (data.position() == 0) { size = data.limit(); } else { size = data.position(); } StringBuilder sb = new StringBuilder(); for (int i = 0; i < size; i++) { byte c = data.get(i); if (i > 0) { sb.append(' '); } sb.append(toHexDumpString(c)); } return sb; } /** * Computes a hex string like 0x00 * * @param data * @return */ static public String toPrintHexDumpString(Byte data) { if (data != null) { return "0x" + String.format("%02X", (0xFF & data)); } return null; } /** * Convert to unsigned int * * @param v * @return */ public static int uint(byte v) { return v & 0xFF; } }