diff -r 000000000000 -r 29b1cd4cb562 bluetooth/btstack/rfcomm/Rfcommfcs.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/bluetooth/btstack/rfcomm/Rfcommfcs.cpp Fri Jan 15 08:13:17 2010 +0200 @@ -0,0 +1,93 @@ +// Copyright (c) 1999-2009 Nokia Corporation and/or its subsidiary(-ies). +// All rights reserved. +// This component and the accompanying materials are made available +// under the terms of "Eclipse Public License v1.0" +// which accompanies this distribution, and is available +// at the URL "http://www.eclipse.org/legal/epl-v10.html". +// +// Initial Contributors: +// Nokia Corporation - initial contribution. +// +// Contributors: +// +// Description: +// Calculation for the RFCOMM (TS07.10) FCS +// +// + +#include +#include "rfcommfcs.h" +#include "debug.h" + +#pragma warning( disable : 4244) // Conv from int to char + +/* + This table is lifted from the TS07.10 spec in the appendices. +*/ + +static const TUint8 crctable[256] = { //reversed, 8-bit, poly=0x07 +0x00, 0x91, 0xE3, 0x72, 0x07, 0x96, 0xE4, 0x75, 0x0E, 0x9F, 0xED, 0x7C, 0x09, 0x98, 0xEA, 0x7B, +0x1C, 0x8D, 0xFF, 0x6E, 0x1B, 0x8A, 0xF8, 0x69, 0x12, 0x83, 0xF1, 0x60, 0x15, 0x84, 0xF6, 0x67, +0x38, 0xA9, 0xDB, 0x4A, 0x3F, 0xAE, 0xDC, 0x4D, 0x36, 0xA7, 0xD5, 0x44, 0x31, 0xA0, 0xD2, 0x43, +0x24, 0xB5, 0xC7, 0x56, 0x23, 0xB2, 0xC0, 0x51, 0x2A, 0xBB, 0xC9, 0x58, 0x2D, 0xBC, 0xCE, 0x5F, +0x70, 0xE1, 0x93, 0x02, 0x77, 0xE6, 0x94, 0x05, 0x7E, 0xEF, 0x9D, 0x0C, 0x79, 0xE8, 0x9A, 0x0B, +0x6C, 0xFD, 0x8F, 0x1E, 0x6B, 0xFA, 0x88, 0x19, 0x62, 0xF3, 0x81, 0x10, 0x65, 0xF4, 0x86, 0x17, +0x48, 0xD9, 0xAB, 0x3A, 0x4F, 0xDE, 0xAC, 0x3D, 0x46, 0xD7, 0xA5, 0x34, 0x41, 0xD0, 0xA2, 0x33, +0x54, 0xC5, 0xB7, 0x26, 0x53, 0xC2, 0xB0, 0x21, 0x5A, 0xCB, 0xB9, 0x28, 0x5D, 0xCC, 0xBE, 0x2F, +0xE0, 0x71, 0x03, 0x92, 0xE7, 0x76, 0x04, 0x95, 0xEE, 0x7F, 0x0D, 0x9C, 0xE9, 0x78, 0x0A, 0x9B, +0xFC, 0x6D, 0x1F, 0x8E, 0xFB, 0x6A, 0x18, 0x89, 0xF2, 0x63, 0x11, 0x80, 0xF5, 0x64, 0x16, 0x87, +0xD8, 0x49, 0x3B, 0xAA, 0xDF, 0x4E, 0x3C, 0xAD, 0xD6, 0x47, 0x35, 0xA4, 0xD1, 0x40, 0x32, 0xA3, +0xC4, 0x55, 0x27, 0xB6, 0xC3, 0x52, 0x20, 0xB1, 0xCA, 0x5B, 0x29, 0xB8, 0xCD, 0x5C, 0x2E, 0xBF, +0x90, 0x01, 0x73, 0xE2, 0x97, 0x06, 0x74, 0xE5, 0x9E, 0x0F, 0x7D, 0xEC, 0x99, 0x08, 0x7A, 0xEB, +0x8C, 0x1D, 0x6F, 0xFE, 0x8B, 0x1A, 0x68, 0xF9, 0x82, 0x13, 0x61, 0xF0, 0x85, 0x14, 0x66, 0xF7, +0xA8, 0x39, 0x4B, 0xDA, 0xAF, 0x3E, 0x4C, 0xDD, 0xA6, 0x37, 0x45, 0xD4, 0xA1, 0x30, 0x42, 0xD3, +0xB4, 0x25, 0x57, 0xC6, 0xB3, 0x22, 0x50, 0xC1, 0xBA, 0x2B, 0x59, 0xC8, 0xBD, 0x2C, 0x5E, 0xCF +}; + + +TUint8 CalcFCS(const TUint8* aData, TInt aLen) + /** + Calculates the FCS over data starting at aData and of length + aLen. Uses the algorithm from the TS07.10 spec. + **/ + { + TUint8 fcs=0xff; + + while(aLen--) + { + fcs=crctable[fcs^*aData++]; + } + + fcs=~fcs; + return fcs; + } + +TBool CheckFCS(const TUint8* aData, TInt aLen, TUint8 aFCS) + /** + Check a received FCS. + **/ + { + TUint8 fcs=0xFF; + while (aLen--) + { + fcs=crctable[fcs^*aData++]; + } + /*Ones complement*/ + fcs=crctable[fcs^aFCS]; +// log "PDU FCS:" aFCS - Shehla + RFQBLOG(KBlogTypeFCS, Log(KBlogActualFCS, aFCS)); +// log this as "Calculated FCS (should be 0xCF): " fcs - Shehla + RFQBLOG(KBlogTypeFCS, Log(KBlogComputedFCS, fcs)); + /*0xCF is the reversed order of 11110011.*/ + TBool result=EFalse; //- Shehla + if (fcs==0xCF) + //return ETrue; + result=ETrue; + else + //return EFalse; + result=EFalse; +//log "FCS Computation" result - Shehla + RFQBLOG(KBlogTypeFCS, Log(KBlogComparedFCS, result)); + + return result; +}