[proxmark3-svn] / client / cmddata.c

//-----------------------------------------------------------------------------
// Copyright (C) 2010 iZsh <izsh at fail0verflow.com>
//
// This code is licensed to you under the terms of the GNU GPL, version 2 or,
// at your option, any later version. See the LICENSE.txt file for the text of
// the license.
//-----------------------------------------------------------------------------
// Data and Graph commands
//-----------------------------------------------------------------------------

#include <stdio.h>    // also included in util.h
#include <string.h>   // also included in util.h
#include <inttypes.h>
#include <limits.h>   // for CmdNorm INT_MIN && INT_MAX
#include "data.h"     // also included in util.h
#include "cmddata.h"
#include "util.h"
#include "cmdmain.h"
#include "proxmark3.h"
#include "ui.h"       // for show graph controls
#include "graph.h"    // for graph data
#include "cmdparser.h"// already included in cmdmain.h
#include "usb_cmd.h"  // already included in cmdmain.h and proxmark3.h
#include "lfdemod.h"  // for demod code
#include "loclass/cipherutils.h" // for decimating samples in getsamples
#include "cmdlfem4x.h"// for em410x demod

uint8_t DemodBuffer[MAX_DEMOD_BUF_LEN];
uint8_t g_debugMode=0;
size_t DemodBufferLen=0;

static int CmdHelp(const char *Cmd);

//set the demod buffer with given array of binary (one bit per byte)
//by marshmellow
void setDemodBuf(uint8_t *buff, size_t size, size_t startIdx)
{
        if (buff == NULL) 
                return;

        if ( size > MAX_DEMOD_BUF_LEN - startIdx)
                size = MAX_DEMOD_BUF_LEN - startIdx;

        size_t i = 0;
        for (; i < size; i++){
                DemodBuffer[i]=buff[startIdx++];
        }
        DemodBufferLen=size;
        return;
}

bool getDemodBuf(uint8_t *buff, size_t *size) {
        if (buff == NULL) return false;
        if (size == NULL) return false;
        if (*size == 0) return false;

        *size = (*size > DemodBufferLen) ? DemodBufferLen : *size;

        memcpy(buff, DemodBuffer, *size);
        return true;
}

// option '1' to save DemodBuffer any other to restore
void save_restoreDB(uint8_t saveOpt)
{
        static uint8_t SavedDB[MAX_DEMOD_BUF_LEN];
        static size_t SavedDBlen;
        static bool DB_Saved = false;

        if (saveOpt==1) { //save

                memcpy(SavedDB, DemodBuffer, sizeof(DemodBuffer));
                SavedDBlen = DemodBufferLen;
                DB_Saved=true;
        } else if (DB_Saved) { //restore
                memcpy(DemodBuffer, SavedDB, sizeof(DemodBuffer));
                DemodBufferLen = SavedDBlen;
        }
        return;
}

int CmdSetDebugMode(const char *Cmd)
{
        int demod=0;
        sscanf(Cmd, "%i", &demod);
        g_debugMode=(uint8_t)demod;
        return 1;
}

int usage_data_printdemodbuf(){
                PrintAndLog("Usage: data printdemodbuffer x o <offset> l <length>");
                PrintAndLog("Options:        ");
                PrintAndLog("       h          This help");
                PrintAndLog("       x          output in hex (omit for binary output)");
                PrintAndLog("       o <offset> enter offset in # of bits");
                PrintAndLog("       l <length> enter length to print in # of bits or hex characters respectively");
                return 0;       
}

//by marshmellow
void printDemodBuff(void)
{
        int bitLen = DemodBufferLen;
        if (bitLen<1) {
                PrintAndLog("no bits found in demod buffer");
                return;
        }
        if (bitLen>512) bitLen=512; //max output to 512 bits if we have more - should be plenty

        char *bin = sprint_bin_break(DemodBuffer,bitLen,16);
        PrintAndLog("%s",bin);

        return;
}

int CmdPrintDemodBuff(const char *Cmd)
{
        char hex[512]={0x00};
        bool hexMode = false;
        bool errors = false;
        uint32_t offset = 0; //could be size_t but no param_get16...
        uint32_t length = 512;
        char cmdp = 0;
        while(param_getchar(Cmd, cmdp) != 0x00)
        {
                switch(param_getchar(Cmd, cmdp))
                {
                case 'h':
                case 'H':
                        return usage_data_printdemodbuf();
                case 'x':
                case 'X':
                        hexMode = true;
                        cmdp++;
                        break;
                case 'o':
                case 'O':
                        offset = param_get32ex(Cmd, cmdp+1, 0, 10);
                        if (!offset) errors = true;
                        cmdp += 2;
                        break;
                case 'l':
                case 'L':
                        length = param_get32ex(Cmd, cmdp+1, 512, 10);
                        if (!length) errors = true;
                        cmdp += 2;
                        break;
                default:
                        PrintAndLog("Unknown parameter '%c'", param_getchar(Cmd, cmdp));
                        errors = true;
                        break;
                }
                if(errors) break;
        }
        //Validations
        if(errors) return usage_data_printdemodbuf();
        length = (length > (DemodBufferLen-offset)) ? DemodBufferLen-offset : length; 
        int numBits = (length) & 0x00FFC; //make sure we don't exceed our string

        if (hexMode){
                char *buf = (char *) (DemodBuffer + offset);
                numBits = (numBits > sizeof(hex)) ? sizeof(hex) : numBits;
                numBits = binarraytohex(hex, buf, numBits);
                if (numBits==0) return 0;
                PrintAndLog("DemodBuffer: %s",hex);             
        } else {
                PrintAndLog("DemodBuffer:\n%s", sprint_bin_break(DemodBuffer+offset,numBits,16));
        }
        return 1;
}

//by marshmellow
//this function strictly converts >1 to 1 and <1 to 0 for each sample in the graphbuffer
int CmdGetBitStream(const char *Cmd)
{
        int i;
        CmdHpf(Cmd);
        for (i = 0; i < GraphTraceLen; i++) {
                if (GraphBuffer[i] >= 1) {
                        GraphBuffer[i] = 1;
                } else {
                        GraphBuffer[i] = 0;
                }
        }
        RepaintGraphWindow();
        return 0;
}

//by marshmellow
//Cmd Args: Clock, invert, maxErr, maxLen as integers and amplify as char == 'a'
//   (amp may not be needed anymore)
//verbose will print results and demoding messages
//emSearch will auto search for EM410x format in bitstream
//askType switches decode: ask/raw = 0, ask/manchester = 1 
int ASKDemod_ext(const char *Cmd, bool verbose, bool emSearch, uint8_t askType, bool *stCheck) {
        int invert=0;
        int clk=0;
        int maxErr=100;
        int maxLen=0;
        uint8_t askamp = 0;
        char amp = param_getchar(Cmd, 0);
        uint8_t BitStream[MAX_GRAPH_TRACE_LEN]={0};
        sscanf(Cmd, "%i %i %i %i %c", &clk, &invert, &maxErr, &maxLen, &amp);
        if (!maxLen) maxLen = BIGBUF_SIZE;
        if (invert != 0 && invert != 1) {
                PrintAndLog("Invalid argument: %s", Cmd);
                return 0;
        }
        if (clk==1){
                invert=1;
                clk=0;
        }
        size_t BitLen = getFromGraphBuf(BitStream);
        if (g_debugMode) PrintAndLog("DEBUG: Bitlen from grphbuff: %d",BitLen);
        if (BitLen < 255) return 0;
        if (maxLen < BitLen && maxLen != 0) BitLen = maxLen;
        int foundclk = 0;
        //amp before ST check
        if (amp == 'a' || amp == 'A') {
                askAmp(BitStream, BitLen); 
        }
        bool st = false;
        size_t ststart = 0, stend = 0;
        if (*stCheck) st = DetectST(BitStream, &BitLen, &foundclk, &ststart, &stend);
        *stCheck = st;
        if (st) {
                clk = (clk == 0) ? foundclk : clk;
                CursorCPos = ststart;
                CursorDPos = stend;
                if (verbose || g_debugMode) PrintAndLog("\nFound Sequence Terminator - First one is shown by orange and blue graph markers");
                //Graph ST trim (for testing)
                //for (int i = 0; i < BitLen; i++) {
                //      GraphBuffer[i] = BitStream[i]-128;
                //}
                //RepaintGraphWindow();
        }
        int startIdx = 0;
        int errCnt = askdemod_ext(BitStream, &BitLen, &clk, &invert, maxErr, askamp, askType, &startIdx);
        if (errCnt<0 || BitLen<16){  //if fatal error (or -1)
                if (g_debugMode) PrintAndLog("DEBUG: no data found %d, errors:%d, bitlen:%d, clock:%d",errCnt,invert,BitLen,clk);
                return 0;
        }
        if (errCnt > maxErr){
                if (g_debugMode) PrintAndLog("DEBUG: Too many errors found, errors:%d, bits:%d, clock:%d",errCnt, BitLen, clk);
                return 0;
        }
        if (verbose || g_debugMode) PrintAndLog("\nUsing Clock:%d, Invert:%d, Bits Found:%d",clk,invert,BitLen);

        //output
        setDemodBuf(BitStream,BitLen,0);
        setClockGrid(clk, startIdx);

        if (verbose || g_debugMode){
                if (errCnt>0) PrintAndLog("# Errors during Demoding (shown as 7 in bit stream): %d",errCnt);
                if (askType) PrintAndLog("ASK/Manchester - Clock: %d - Decoded bitstream:",clk);
                else PrintAndLog("ASK/Raw - Clock: %d - Decoded bitstream:",clk);
                // Now output the bitstream to the scrollback by line of 16 bits
                printDemodBuff();
                
        }
        uint64_t lo = 0;
        uint32_t hi = 0;
        if (emSearch){
                AskEm410xDecode(true, &hi, &lo);
        }
        return 1;
}
int ASKDemod(const char *Cmd, bool verbose, bool emSearch, uint8_t askType) {
        bool st = false;
        return ASKDemod_ext(Cmd, verbose, emSearch, askType, &st);
}

//by marshmellow
//takes 5 arguments - clock, invert, maxErr, maxLen as integers and amplify as char == 'a'
//attempts to demodulate ask while decoding manchester
//prints binary found and saves in graphbuffer for further commands
int Cmdaskmandemod(const char *Cmd)
{
        char cmdp = param_getchar(Cmd, 0);
        if (strlen(Cmd) > 45 || cmdp == 'h' || cmdp == 'H') {
                PrintAndLog("Usage:  data rawdemod am <s> [clock] <invert> [maxError] [maxLen] [amplify]");
                PrintAndLog("     ['s'] optional, check for Sequence Terminator");
                PrintAndLog("     [set clock as integer] optional, if not set, autodetect");
                PrintAndLog("     <invert>, 1 to invert output");
                PrintAndLog("     [set maximum allowed errors], default = 100");
                PrintAndLog("     [set maximum Samples to read], default = 32768 (512 bits at rf/64)");
                PrintAndLog("     <amplify>, 'a' to attempt demod with ask amplification, default = no amp");
                PrintAndLog("");
                PrintAndLog("    sample: data rawdemod am        = demod an ask/manchester tag from GraphBuffer");
                PrintAndLog("          : data rawdemod am 32     = demod an ask/manchester tag from GraphBuffer using a clock of RF/32");
                PrintAndLog("          : data rawdemod am 32 1   = demod an ask/manchester tag from GraphBuffer using a clock of RF/32 and inverting data");
                PrintAndLog("          : data rawdemod am 1      = demod an ask/manchester tag from GraphBuffer while inverting data");
                PrintAndLog("          : data rawdemod am 64 1 0 = demod an ask/manchester tag from GraphBuffer using a clock of RF/64, inverting data and allowing 0 demod errors");
                return 0;
        }
        bool st = true;
        if (Cmd[0]=='s') 
                return ASKDemod_ext(Cmd++, true, true, 1, &st);
        else if (Cmd[1] == 's')
                return ASKDemod_ext(Cmd+=2, true, true, 1, &st);
        else
                return ASKDemod(Cmd, true, true, 1);
}

//by marshmellow
//manchester decode
//stricktly take 10 and 01 and convert to 0 and 1
int Cmdmandecoderaw(const char *Cmd)
{
        int i =0;
        int errCnt=0;
        size_t size=0;
        int invert=0;
        int maxErr = 20;
        char cmdp = param_getchar(Cmd, 0);
        if (strlen(Cmd) > 5 || cmdp == 'h' || cmdp == 'H') {
                PrintAndLog("Usage:  data manrawdecode [invert] [maxErr]");
                PrintAndLog("     Takes 10 and 01 and converts to 0 and 1 respectively");
                PrintAndLog("     --must have binary sequence in demodbuffer (run data askrawdemod first)");
                PrintAndLog("  [invert]  invert output");               
                PrintAndLog("  [maxErr]  set number of errors allowed (default = 20)");         
                PrintAndLog("");
                PrintAndLog("    sample: data manrawdecode   = decode manchester bitstream from the demodbuffer");
                return 0;
        }
        if (DemodBufferLen==0) return 0;
        uint8_t BitStream[MAX_DEMOD_BUF_LEN]={0};
        int high=0,low=0;
        for (;i<DemodBufferLen;++i){
                if (DemodBuffer[i]>high) high=DemodBuffer[i];
                else if(DemodBuffer[i]<low) low=DemodBuffer[i];
                BitStream[i]=DemodBuffer[i];
        }
        if (high>7 || low <0 ){
                PrintAndLog("Error: please raw demod the wave first then manchester raw decode");
                return 0;
        }

        sscanf(Cmd, "%i %i", &invert, &maxErr);
        size=i;
        uint8_t alignPos = 0;
        errCnt=manrawdecode(BitStream, &size, invert, &alignPos);
        if (errCnt>=maxErr){
                PrintAndLog("Too many errors: %d",errCnt);
                return 0;
        }
        PrintAndLog("Manchester Decoded - # errors:%d - data:",errCnt);
        PrintAndLog("%s", sprint_bin_break(BitStream, size, 16));
        if (errCnt==0){
                uint64_t id = 0;
                uint32_t hi = 0;
                size_t idx=0;
                if (Em410xDecode(BitStream, &size, &idx, &hi, &id)){
                        //need to adjust to set bitstream back to manchester encoded data
                        //setDemodBuf(BitStream, size, idx);

                        printEM410x(hi, id);
                }
        }
        return 1;
}

//by marshmellow
//biphase decode
//take 01 or 10 = 0 and 11 or 00 = 1
//takes 2 arguments "offset" default = 0 if 1 it will shift the decode by one bit
// and "invert" default = 0 if 1 it will invert output
//  the argument offset allows us to manually shift if the output is incorrect - [EDIT: now auto detects]
int CmdBiphaseDecodeRaw(const char *Cmd)
{
        size_t size=0;
        int offset=0, invert=0, maxErr=20, errCnt=0;
        char cmdp = param_getchar(Cmd, 0);
        if (strlen(Cmd) > 3 || cmdp == 'h' || cmdp == 'H') {
                PrintAndLog("Usage:  data biphaserawdecode [offset] [invert] [maxErr]");
                PrintAndLog("     Converts 10 or 01 to 1 and 11 or 00 to 0");
                PrintAndLog("     --must have binary sequence in demodbuffer (run data askrawdemod first)");
                PrintAndLog("     --invert for Conditional Dephase Encoding (CDP) AKA Differential Manchester");
                PrintAndLog("");
                PrintAndLog("     [offset <0|1>], set to 0 not to adjust start position or to 1 to adjust decode start position");
                PrintAndLog("     [invert <0|1>], set to 1 to invert output");
                PrintAndLog("     [maxErr int],   set max errors tolerated - default=20");
                PrintAndLog("");
                PrintAndLog("    sample: data biphaserawdecode     = decode biphase bitstream from the demodbuffer");
                PrintAndLog("    sample: data biphaserawdecode 1 1 = decode biphase bitstream from the demodbuffer, set offset, and invert output");
                return 0;
        }
        sscanf(Cmd, "%i %i %i", &offset, &invert, &maxErr);
        if (DemodBufferLen==0) {
                PrintAndLog("DemodBuffer Empty - run 'data rawdemod ar' first");
                return 0;
        }
        uint8_t BitStream[MAX_DEMOD_BUF_LEN]={0};
        size = sizeof(BitStream);
        if ( !getDemodBuf(BitStream, &size) ) return 0;
        errCnt=BiphaseRawDecode(BitStream, &size, offset, invert);
        if (errCnt<0){
                PrintAndLog("Error during decode:%d", errCnt);
                return 0;
        }
        if (errCnt>maxErr){
                PrintAndLog("Too many errors attempting to decode: %d",errCnt);
                return 0;
        }

        if (errCnt>0){
                PrintAndLog("# Errors found during Demod (shown as 7 in bit stream): %d",errCnt);
        }
        PrintAndLog("Biphase Decoded using offset: %d - # invert:%d - data:",offset,invert);
        PrintAndLog("%s", sprint_bin_break(BitStream, size, 16));
        
        if (offset) setDemodBuf(DemodBuffer,DemodBufferLen-offset, offset);  //remove first bit from raw demod
        return 1;
}

//by marshmellow
// - ASK Demod then Biphase decode GraphBuffer samples
int ASKbiphaseDemod(const char *Cmd, bool verbose)
{
        //ask raw demod GraphBuffer first
        int offset=0, clk=0, invert=0, maxErr=0;
        sscanf(Cmd, "%i %i %i %i", &offset, &clk, &invert, &maxErr);

        uint8_t BitStream[MAX_GRAPH_TRACE_LEN];   
        size_t size = getFromGraphBuf(BitStream);         
        //invert here inverts the ask raw demoded bits which has no effect on the demod, but we need the pointer
        int errCnt = askdemod(BitStream, &size, &clk, &invert, maxErr, 0, 0);  
        if ( errCnt < 0 || errCnt > maxErr ) {   
                if (g_debugMode) PrintAndLog("DEBUG: no data or error found %d, clock: %d", errCnt, clk);  
                        return 0;  
        } 

        //attempt to Biphase decode BitStream
        errCnt = BiphaseRawDecode(BitStream, &size, offset, invert);
        if (errCnt < 0){
                if (g_debugMode || verbose) PrintAndLog("Error BiphaseRawDecode: %d", errCnt);
                return 0;
        } 
        if (errCnt > maxErr) {
                if (g_debugMode || verbose) PrintAndLog("Error BiphaseRawDecode too many errors: %d", errCnt);
                return 0;
        }
        //success set DemodBuffer and return
        setDemodBuf(BitStream, size, 0);
        if (g_debugMode || verbose){
                PrintAndLog("Biphase Decoded using offset: %d - clock: %d - # errors:%d - data:",offset,clk,errCnt);
                printDemodBuff();
        }
        return 1;
}
//by marshmellow - see ASKbiphaseDemod
int Cmdaskbiphdemod(const char *Cmd)
{
        char cmdp = param_getchar(Cmd, 0);
        if (strlen(Cmd) > 25 || cmdp == 'h' || cmdp == 'H') {
                PrintAndLog("Usage:  data rawdemod ab [offset] [clock] <invert> [maxError] [maxLen] <amplify>");
                PrintAndLog("     [offset], offset to begin biphase, default=0");
                PrintAndLog("     [set clock as integer] optional, if not set, autodetect");
                PrintAndLog("     <invert>, 1 to invert output");
                PrintAndLog("     [set maximum allowed errors], default = 100");
                PrintAndLog("     [set maximum Samples to read], default = 32768 (512 bits at rf/64)");
                PrintAndLog("     <amplify>, 'a' to attempt demod with ask amplification, default = no amp");
                PrintAndLog("     NOTE: <invert>  can be entered as second or third argument");
                PrintAndLog("     NOTE: <amplify> can be entered as first, second or last argument");
                PrintAndLog("     NOTE: any other arg must have previous args set to work");
                PrintAndLog("");
                PrintAndLog("     NOTE: --invert for Conditional Dephase Encoding (CDP) AKA Differential Manchester");
                PrintAndLog("");
                PrintAndLog("    sample: data rawdemod ab              = demod an ask/biph tag from GraphBuffer");
                PrintAndLog("          : data rawdemod ab 0 a          = demod an ask/biph tag from GraphBuffer, amplified");
                PrintAndLog("          : data rawdemod ab 1 32         = demod an ask/biph tag from GraphBuffer using an offset of 1 and a clock of RF/32");
                PrintAndLog("          : data rawdemod ab 0 32 1       = demod an ask/biph tag from GraphBuffer using a clock of RF/32 and inverting data");
                PrintAndLog("          : data rawdemod ab 0 1          = demod an ask/biph tag from GraphBuffer while inverting data");
                PrintAndLog("          : data rawdemod ab 0 64 1 0     = demod an ask/biph tag from GraphBuffer using a clock of RF/64, inverting data and allowing 0 demod errors");
                PrintAndLog("          : data rawdemod ab 0 64 1 0 0 a = demod an ask/biph tag from GraphBuffer using a clock of RF/64, inverting data and allowing 0 demod errors, and amp");
                return 0;
        }
        return ASKbiphaseDemod(Cmd, true);
}

//by marshmellow - see ASKDemod
int Cmdaskrawdemod(const char *Cmd)
{
        char cmdp = param_getchar(Cmd, 0);
        if (strlen(Cmd) > 35 || cmdp == 'h' || cmdp == 'H') {
                PrintAndLog("Usage:  data rawdemod ar [clock] <invert> [maxError] [maxLen] [amplify]");
                PrintAndLog("     [set clock as integer] optional, if not set, autodetect");
                PrintAndLog("     <invert>, 1 to invert output");
                PrintAndLog("     [set maximum allowed errors], default = 100");
                PrintAndLog("     [set maximum Samples to read], default = 32768 (1024 bits at rf/64)");
                PrintAndLog("     <amplify>, 'a' to attempt demod with ask amplification, default = no amp");
                PrintAndLog("");
                PrintAndLog("    sample: data rawdemod ar            = demod an ask tag from GraphBuffer");
                PrintAndLog("          : data rawdemod ar a          = demod an ask tag from GraphBuffer, amplified");
                PrintAndLog("          : data rawdemod ar 32         = demod an ask tag from GraphBuffer using a clock of RF/32");
                PrintAndLog("          : data rawdemod ar 32 1       = demod an ask tag from GraphBuffer using a clock of RF/32 and inverting data");
                PrintAndLog("          : data rawdemod ar 1          = demod an ask tag from GraphBuffer while inverting data");
                PrintAndLog("          : data rawdemod ar 64 1 0     = demod an ask tag from GraphBuffer using a clock of RF/64, inverting data and allowing 0 demod errors");
                PrintAndLog("          : data rawdemod ar 64 1 0 0 a = demod an ask tag from GraphBuffer using a clock of RF/64, inverting data and allowing 0 demod errors, and amp");
                return 0;
        }
        return ASKDemod(Cmd, true, false, 0);
}

int AutoCorrelate(int window, bool SaveGrph, bool verbose)
{
        static int CorrelBuffer[MAX_GRAPH_TRACE_LEN];
        size_t Correlation = 0;
        int maxSum = 0;
        int lastMax = 0;
        if (verbose) PrintAndLog("performing %d correlations", GraphTraceLen - window);
        for (int i = 0; i < GraphTraceLen - window; ++i) {
                int sum = 0;
                for (int j = 0; j < window; ++j) {
                        sum += (GraphBuffer[j]*GraphBuffer[i + j]) / 256;
                }
                CorrelBuffer[i] = sum;
                if (sum >= maxSum-100 && sum <= maxSum+100){
                        //another max
                        Correlation = i-lastMax;
                        lastMax = i;
                        if (sum > maxSum) maxSum = sum;
                } else if (sum > maxSum){
                        maxSum=sum;
                        lastMax = i;
                }
        }
        if (Correlation==0){
                //try again with wider margin
                for (int i = 0; i < GraphTraceLen - window; i++){
                        if (CorrelBuffer[i] >= maxSum-(maxSum*0.05) && CorrelBuffer[i] <= maxSum+(maxSum*0.05)){
                                //another max
                                Correlation = i-lastMax;
                                lastMax = i;
                                //if (CorrelBuffer[i] > maxSum) maxSum = sum;
                        }
                }
        }
        if (verbose && Correlation > 0) PrintAndLog("Possible Correlation: %d samples",Correlation);

        if (SaveGrph){
                GraphTraceLen = GraphTraceLen - window;
                memcpy(GraphBuffer, CorrelBuffer, GraphTraceLen * sizeof (int));
                RepaintGraphWindow();  
        }
        return Correlation;
}

int usage_data_autocorr(void)
{
        //print help
        PrintAndLog("Usage: data autocorr [window] [g]");
        PrintAndLog("Options:        ");
        PrintAndLog("       h              This help");
        PrintAndLog("       [window]       window length for correlation - default = 4000");
        PrintAndLog("       g              save back to GraphBuffer (overwrite)");
        return 0;
}

int CmdAutoCorr(const char *Cmd)
{
        char cmdp = param_getchar(Cmd, 0);
        if (cmdp == 'h' || cmdp == 'H') 
                return usage_data_autocorr();
        int window = 4000; //set default
        char grph=0;
        bool updateGrph = false;
        sscanf(Cmd, "%i %c", &window, &grph);

        if (window >= GraphTraceLen) {
                PrintAndLog("window must be smaller than trace (%d samples)",
                        GraphTraceLen);
                return 0;
        }
        if (grph == 'g') updateGrph=true;
        return AutoCorrelate(window, updateGrph, true);
}

int CmdBitsamples(const char *Cmd)
{
        int cnt = 0;
        uint8_t got[12288];

        GetFromBigBuf(got,sizeof(got),0);
        WaitForResponse(CMD_ACK,NULL);

                for (int j = 0; j < sizeof(got); j++) {
                        for (int k = 0; k < 8; k++) {
                                if(got[j] & (1 << (7 - k))) {
                                        GraphBuffer[cnt++] = 1;
                                } else {
                                        GraphBuffer[cnt++] = 0;
                                }
                        }
        }
        GraphTraceLen = cnt;
        RepaintGraphWindow();
        return 0;
}

int CmdBuffClear(const char *Cmd)
{
        UsbCommand c = {CMD_BUFF_CLEAR};
        SendCommand(&c);
        ClearGraph(true);
        return 0;
}

int CmdDec(const char *Cmd)
{
        for (int i = 0; i < (GraphTraceLen / 2); ++i)
                GraphBuffer[i] = GraphBuffer[i * 2];
        GraphTraceLen /= 2;
        PrintAndLog("decimated by 2");
        RepaintGraphWindow();
        return 0;
}
/**
 * Undecimate - I'd call it 'interpolate', but we'll save that
 * name until someone does an actual interpolation command, not just
 * blindly repeating samples
 * @param Cmd
 * @return
 */
int CmdUndec(const char *Cmd)
{
        if(param_getchar(Cmd, 0) == 'h')
        {
                PrintAndLog("Usage: data undec [factor]");
                PrintAndLog("This function performs un-decimation, by repeating each sample N times");
                PrintAndLog("Options:        ");
                PrintAndLog("       h            This help");
                PrintAndLog("       factor       The number of times to repeat each sample.[default:2]");
                PrintAndLog("Example: 'data undec 3'");
                return 0;
        }

        uint8_t factor = param_get8ex(Cmd, 0,2, 10);
        //We have memory, don't we?
        int swap[MAX_GRAPH_TRACE_LEN] = { 0 };
        uint32_t g_index = 0, s_index = 0;
        while(g_index < GraphTraceLen && s_index + factor < MAX_GRAPH_TRACE_LEN)
        {
                int count = 0;
                for(count = 0; count < factor && s_index + count < MAX_GRAPH_TRACE_LEN; count++)
                        swap[s_index+count] = GraphBuffer[g_index];

                s_index += count;
                g_index++;
        }

        memcpy(GraphBuffer, swap, s_index * sizeof(int));
        GraphTraceLen = s_index;
        RepaintGraphWindow();
        return 0;
}

//by marshmellow
//shift graph zero up or down based on input + or -
int CmdGraphShiftZero(const char *Cmd)
{

        int shift=0;
        //set options from parameters entered with the command
        sscanf(Cmd, "%i", &shift);
        int shiftedVal=0;
        for(int i = 0; i<GraphTraceLen; i++){
                shiftedVal=GraphBuffer[i]+shift;
                if (shiftedVal>127) 
                        shiftedVal=127;
                else if (shiftedVal<-127) 
                        shiftedVal=-127;
                GraphBuffer[i]= shiftedVal;
        }
        CmdNorm("");
        return 0;
}

//by marshmellow
//use large jumps in read samples to identify edges of waves and then amplify that wave to max
//similar to dirtheshold, threshold commands 
//takes a threshold length which is the measured length between two samples then determines an edge
int CmdAskEdgeDetect(const char *Cmd)
{
        int thresLen = 25;
        int Last = 0;
        sscanf(Cmd, "%i", &thresLen); 

        for(int i = 1; i<GraphTraceLen; i++){
                if (GraphBuffer[i]-GraphBuffer[i-1]>=thresLen) //large jump up
                        Last = 127;
                else if(GraphBuffer[i]-GraphBuffer[i-1]<=-1*thresLen) //large jump down
                        Last = -127;
                GraphBuffer[i-1] = Last;
        }
        RepaintGraphWindow();
        return 0;
}

/* Print our clock rate */
// uses data from graphbuffer
// adjusted to take char parameter for type of modulation to find the clock - by marshmellow.
int CmdDetectClockRate(const char *Cmd)
{
        char cmdp = param_getchar(Cmd, 0);
        if (strlen(Cmd) > 6 || strlen(Cmd) == 0 || cmdp == 'h' || cmdp == 'H') {
                PrintAndLog("Usage:  data detectclock [modulation] <clock>");
                PrintAndLog("     [modulation as char], specify the modulation type you want to detect the clock of");
                PrintAndLog("     <clock>             , specify the clock (optional - to get best start position only)");
                PrintAndLog("       'a' = ask, 'f' = fsk, 'n' = nrz/direct, 'p' = psk");
                PrintAndLog("");
                PrintAndLog("    sample: data detectclock a    = detect the clock of an ask modulated wave in the GraphBuffer");
                PrintAndLog("            data detectclock f    = detect the clock of an fsk modulated wave in the GraphBuffer");
                PrintAndLog("            data detectclock p    = detect the clock of an psk modulated wave in the GraphBuffer");
                PrintAndLog("            data detectclock n    = detect the clock of an nrz/direct modulated wave in the GraphBuffer");
        }
        int ans=0;
        if (cmdp == 'a'){
                ans = GetAskClock(Cmd+1, true, false);
        } else if (cmdp == 'f'){
                ans = GetFskClock("", true, false);
        } else if (cmdp == 'n'){
                ans = GetNrzClock("", true, false);
        } else if (cmdp == 'p'){
                ans = GetPskClock("", true, false);
        } else {
                PrintAndLog ("Please specify a valid modulation to detect the clock of - see option h for help");
        }
        return ans;
}

char *GetFSKType(uint8_t fchigh, uint8_t fclow, uint8_t invert)
{
        static char fType[8];
        memset(fType, 0x00, 8);
        char *fskType = fType;
        if (fchigh==10 && fclow==8){
                if (invert) //fsk2a
                        memcpy(fskType, "FSK2a", 5);
                else //fsk2
                        memcpy(fskType, "FSK2", 4);
        } else if (fchigh == 8 && fclow == 5) {
                if (invert)
                        memcpy(fskType, "FSK1", 4);
                else
                        memcpy(fskType, "FSK1a", 5);
        } else {
                memcpy(fskType, "FSK??", 5);
        }
        return fskType;
}

//by marshmellow
//fsk raw demod and print binary
//takes 4 arguments - Clock, invert, fchigh, fclow
//defaults: clock = 50, invert=1, fchigh=10, fclow=8 (RF/10 RF/8 (fsk2a))
int FSKrawDemod(const char *Cmd, bool verbose)
{
        //raw fsk demod  no manchester decoding no start bit finding just get binary from wave
        uint8_t rfLen, invert, fchigh, fclow;
        //set defaults
        //set options from parameters entered with the command
        rfLen = param_get8(Cmd, 0);
        invert = param_get8(Cmd, 1);
        fchigh = param_get8(Cmd, 2);
        fclow = param_get8(Cmd, 3);

        if (strlen(Cmd)>0 && strlen(Cmd)<=2) {
                if (rfLen==1) {
                        invert = 1;   //if invert option only is used
                        rfLen = 0;
                }
        }
        uint8_t BitStream[MAX_GRAPH_TRACE_LEN]={0};
        size_t BitLen = getFromGraphBuf(BitStream);
        if (BitLen==0) return 0;
        //get field clock lengths
        uint16_t fcs=0;
        if (!fchigh || !fclow) {
                fcs = countFC(BitStream, BitLen, 1);
                if (!fcs) {
                        fchigh = 10;
                        fclow = 8;
                } else {
                        fchigh = (fcs >> 8) & 0x00FF;
                        fclow = fcs & 0x00FF;
                }
        }
        //get bit clock length
        if (!rfLen) {
                int firstClockEdge = 0; //todo - align grid on graph with this...
                rfLen = detectFSKClk(BitStream, BitLen, fchigh, fclow, &firstClockEdge);
                if (!rfLen) rfLen = 50;
        }
        int startIdx = 0;
        int size = fskdemod_ext(BitStream, BitLen, rfLen, invert, fchigh, fclow, &startIdx);
        if (size > 0) {
                setDemodBuf(BitStream,size,0);
                setClockGrid(rfLen, startIdx);

                // Now output the bitstream to the scrollback by line of 16 bits
                if (verbose || g_debugMode) {
                        PrintAndLog("\nUsing Clock:%u, invert:%u, fchigh:%u, fclow:%u", (unsigned int)rfLen, (unsigned int)invert, (unsigned int)fchigh, (unsigned int)fclow);
                        PrintAndLog("%s decoded bitstream:",GetFSKType(fchigh,fclow,invert));
                        printDemodBuff();
                }

                return 1;
        } else {
                if (g_debugMode) PrintAndLog("no FSK data found");
        }
        return 0;
}

//by marshmellow
//fsk raw demod and print binary
//takes 4 arguments - Clock, invert, fchigh, fclow
//defaults: clock = 50, invert=1, fchigh=10, fclow=8 (RF/10 RF/8 (fsk2a))
int CmdFSKrawdemod(const char *Cmd)
{
        char cmdp = param_getchar(Cmd, 0);
        if (strlen(Cmd) > 20 || cmdp == 'h' || cmdp == 'H') {
                PrintAndLog("Usage:  data rawdemod fs [clock] <invert> [fchigh] [fclow]");
                PrintAndLog("     [set clock as integer] optional, omit for autodetect.");
                PrintAndLog("     <invert>, 1 for invert output, can be used even if the clock is omitted");
                PrintAndLog("     [fchigh], larger field clock length, omit for autodetect");
                PrintAndLog("     [fclow], small field clock length, omit for autodetect");
                PrintAndLog("");
                PrintAndLog("    sample: data rawdemod fs           = demod an fsk tag from GraphBuffer using autodetect");
                PrintAndLog("          : data rawdemod fs 32        = demod an fsk tag from GraphBuffer using a clock of RF/32, autodetect fc");
                PrintAndLog("          : data rawdemod fs 1         = demod an fsk tag from GraphBuffer using autodetect, invert output");   
                PrintAndLog("          : data rawdemod fs 32 1      = demod an fsk tag from GraphBuffer using a clock of RF/32, invert output, autodetect fc");
                PrintAndLog("          : data rawdemod fs 64 0 8 5  = demod an fsk1 RF/64 tag from GraphBuffer");
                PrintAndLog("          : data rawdemod fs 50 0 10 8 = demod an fsk2 RF/50 tag from GraphBuffer");
                PrintAndLog("          : data rawdemod fs 50 1 10 8 = demod an fsk2a RF/50 tag from GraphBuffer");
                return 0;
        }
        return FSKrawDemod(Cmd, true);
}

//by marshmellow
//attempt to psk1 demod graph buffer
int PSKDemod(const char *Cmd, bool verbose)
{
        int invert=0;
        int clk=0;
        int maxErr=100;
        sscanf(Cmd, "%i %i %i", &clk, &invert, &maxErr);
        if (clk==1){
                invert=1;
                clk=0;
        }
        if (invert != 0 && invert != 1) {
                if (g_debugMode || verbose) PrintAndLog("Invalid argument: %s", Cmd);
                return 0;
        }
        uint8_t BitStream[MAX_GRAPH_TRACE_LEN]={0};
        size_t BitLen = getFromGraphBuf(BitStream);
        if (BitLen==0) return 0;
        int errCnt=0;
        int startIdx = 0;
        errCnt = pskRawDemod_ext(BitStream, &BitLen, &clk, &invert, &startIdx);
        if (errCnt > maxErr){
                if (g_debugMode || verbose) PrintAndLog("Too many errors found, clk: %d, invert: %d, numbits: %d, errCnt: %d",clk,invert,BitLen,errCnt);
                return 0;
        } 
        if (errCnt<0|| BitLen<16){  //throw away static - allow 1 and -1 (in case of threshold command first)
                if (g_debugMode || verbose) PrintAndLog("no data found, clk: %d, invert: %d, numbits: %d, errCnt: %d",clk,invert,BitLen,errCnt);
                return 0;
        }
        if (verbose || g_debugMode){
                PrintAndLog("\nUsing Clock:%d, invert:%d, Bits Found:%d",clk,invert,BitLen);
                if (errCnt>0){
                        PrintAndLog("# Errors during Demoding (shown as 7 in bit stream): %d",errCnt);
                }
        }
        //prime demod buffer for output
        setDemodBuf(BitStream,BitLen,0);
        setClockGrid(clk, startIdx);

        return 1;
}

// by marshmellow
// takes 3 arguments - clock, invert, maxErr as integers
// attempts to demodulate nrz only
// prints binary found and saves in demodbuffer for further commands
int NRZrawDemod(const char *Cmd, bool verbose)
{
        int invert=0;
        int clk=0;
        int maxErr=100;
        sscanf(Cmd, "%i %i %i", &clk, &invert, &maxErr);
        if (clk==1){
                invert=1;
                clk=0;
        }
        if (invert != 0 && invert != 1) {
                PrintAndLog("Invalid argument: %s", Cmd);
                return 0;
        }
        uint8_t BitStream[MAX_GRAPH_TRACE_LEN]={0};
        size_t BitLen = getFromGraphBuf(BitStream);
        if (BitLen==0) return 0;
        int errCnt=0;
        int clkStartIdx = 0;
        errCnt = nrzRawDemod(BitStream, &BitLen, &clk, &invert, &clkStartIdx);
        if (errCnt > maxErr){
                if (g_debugMode) PrintAndLog("Too many errors found, clk: %d, invert: %d, numbits: %d, errCnt: %d",clk,invert,BitLen,errCnt);
                return 0;
        } 
        if (errCnt<0 || BitLen<16){  //throw away static - allow 1 and -1 (in case of threshold command first)
                if (g_debugMode) PrintAndLog("no data found, clk: %d, invert: %d, numbits: %d, errCnt: %d",clk,invert,BitLen,errCnt);
                return 0;
        }
        if (verbose || g_debugMode) PrintAndLog("Tried NRZ Demod using Clock: %d - invert: %d - Bits Found: %d",clk,invert,BitLen);
        //prime demod buffer for output
        setDemodBuf(BitStream,BitLen,0);
        setClockGrid(clk, clkStartIdx);


        if (errCnt>0 && (verbose || g_debugMode)) PrintAndLog("# Errors during Demoding (shown as 7 in bit stream): %d",errCnt);
        if (verbose || g_debugMode) {
                PrintAndLog("NRZ demoded bitstream:");
                // Now output the bitstream to the scrollback by line of 16 bits
                printDemodBuff();
        }
        return 1; 
}

int CmdNRZrawDemod(const char *Cmd)
{
        char cmdp = param_getchar(Cmd, 0);
        if (strlen(Cmd) > 16 || cmdp == 'h' || cmdp == 'H') {
                PrintAndLog("Usage:  data rawdemod nr [clock] <0|1> [maxError]");
                PrintAndLog("     [set clock as integer] optional, if not set, autodetect.");
                PrintAndLog("     <invert>, 1 for invert output");
                PrintAndLog("     [set maximum allowed errors], default = 100.");
                PrintAndLog("");
                PrintAndLog("    sample: data rawdemod nr        = demod a nrz/direct tag from GraphBuffer");
                PrintAndLog("          : data rawdemod nr 32     = demod a nrz/direct tag from GraphBuffer using a clock of RF/32");
                PrintAndLog("          : data rawdemod nr 32 1   = demod a nrz/direct tag from GraphBuffer using a clock of RF/32 and inverting data");
                PrintAndLog("          : data rawdemod nr 1      = demod a nrz/direct tag from GraphBuffer while inverting data");
                PrintAndLog("          : data rawdemod nr 64 1 0 = demod a nrz/direct tag from GraphBuffer using a clock of RF/64, inverting data and allowing 0 demod errors");
                return 0;
        }
        return NRZrawDemod(Cmd, true);
}

// by marshmellow
// takes 3 arguments - clock, invert, maxErr as integers
// attempts to demodulate psk only
// prints binary found and saves in demodbuffer for further commands
int CmdPSK1rawDemod(const char *Cmd)
{
        int ans;
        char cmdp = param_getchar(Cmd, 0);
        if (strlen(Cmd) > 16 || cmdp == 'h' || cmdp == 'H') {
                PrintAndLog("Usage:  data rawdemod p1 [clock] <0|1> [maxError]");
                PrintAndLog("     [set clock as integer] optional, if not set, autodetect.");
                PrintAndLog("     <invert>, 1 for invert output");
                PrintAndLog("     [set maximum allowed errors], default = 100.");
                PrintAndLog("");
                PrintAndLog("    sample: data rawdemod p1        = demod a psk1 tag from GraphBuffer");
                PrintAndLog("          : data rawdemod p1 32     = demod a psk1 tag from GraphBuffer using a clock of RF/32");
                PrintAndLog("          : data rawdemod p1 32 1   = demod a psk1 tag from GraphBuffer using a clock of RF/32 and inverting data");
                PrintAndLog("          : data rawdemod p1 1      = demod a psk1 tag from GraphBuffer while inverting data");
                PrintAndLog("          : data rawdemod p1 64 1 0 = demod a psk1 tag from GraphBuffer using a clock of RF/64, inverting data and allowing 0 demod errors");
                return 0;
        }
        ans = PSKDemod(Cmd, true);
        //output
        if (!ans){
                if (g_debugMode) PrintAndLog("Error demoding: %d",ans); 
                return 0;
        }
 
        PrintAndLog("PSK1 demoded bitstream:");
        // Now output the bitstream to the scrollback by line of 16 bits
        printDemodBuff();
        return 1;
}

// by marshmellow
// takes same args as cmdpsk1rawdemod
int CmdPSK2rawDemod(const char *Cmd)
{
        int ans=0;
        char cmdp = param_getchar(Cmd, 0);
        if (strlen(Cmd) > 16 || cmdp == 'h' || cmdp == 'H') {
                PrintAndLog("Usage:  data rawdemod p2 [clock] <0|1> [maxError]");
                PrintAndLog("     [set clock as integer] optional, if not set, autodetect.");
                PrintAndLog("     <invert>, 1 for invert output");
                PrintAndLog("     [set maximum allowed errors], default = 100.");
                PrintAndLog("");
                PrintAndLog("    sample: data rawdemod p2         = demod a psk2 tag from GraphBuffer, autodetect clock");
                PrintAndLog("          : data rawdemod p2 32      = demod a psk2 tag from GraphBuffer using a clock of RF/32");
                PrintAndLog("          : data rawdemod p2 32 1    = demod a psk2 tag from GraphBuffer using a clock of RF/32 and inverting output");
                PrintAndLog("          : data rawdemod p2 1       = demod a psk2 tag from GraphBuffer, autodetect clock and invert output");
                PrintAndLog("          : data rawdemod p2 64 1 0  = demod a psk2 tag from GraphBuffer using a clock of RF/64, inverting output and allowing 0 demod errors");
                return 0;
        }
        ans=PSKDemod(Cmd, true);
        if (!ans){
                if (g_debugMode) PrintAndLog("Error demoding: %d",ans);  
                return 0;
        } 
        psk1TOpsk2(DemodBuffer, DemodBufferLen);
        PrintAndLog("PSK2 demoded bitstream:");
        // Now output the bitstream to the scrollback by line of 16 bits
        printDemodBuff();  
        return 1;
}

// by marshmellow - combines all raw demod functions into one menu command
int CmdRawDemod(const char *Cmd)
{
        char cmdp = Cmd[0]; //param_getchar(Cmd, 0);

        if (strlen(Cmd) > 35 || cmdp == 'h' || cmdp == 'H' || strlen(Cmd)<2) {
                PrintAndLog("Usage:  data rawdemod [modulation] <help>|<options>");
                PrintAndLog("   [modulation] as 2 char, 'ab' for ask/biphase, 'am' for ask/manchester, 'ar' for ask/raw, 'fs' for fsk, ...");           
                PrintAndLog("         'nr' for nrz/direct, 'p1' for psk1, 'p2' for psk2");
                PrintAndLog("   <help> as 'h', prints the help for the specific modulation");   
                PrintAndLog("   <options> see specific modulation help for optional parameters");                               
                PrintAndLog("");
                PrintAndLog("    sample: data rawdemod fs h         = print help specific to fsk demod");
                PrintAndLog("          : data rawdemod fs           = demod GraphBuffer using: fsk - autodetect");
                PrintAndLog("          : data rawdemod ab           = demod GraphBuffer using: ask/biphase - autodetect");
                PrintAndLog("          : data rawdemod am           = demod GraphBuffer using: ask/manchester - autodetect");
                PrintAndLog("          : data rawdemod ar           = demod GraphBuffer using: ask/raw - autodetect");
                PrintAndLog("          : data rawdemod nr           = demod GraphBuffer using: nrz/direct - autodetect");
                PrintAndLog("          : data rawdemod p1           = demod GraphBuffer using: psk1 - autodetect");
                PrintAndLog("          : data rawdemod p2           = demod GraphBuffer using: psk2 - autodetect");
                return 0;
        }
        char cmdp2 = Cmd[1];
        int ans = 0;
        if (cmdp == 'f' && cmdp2 == 's'){
                ans = CmdFSKrawdemod(Cmd+2);
        } else if(cmdp == 'a' && cmdp2 == 'b'){
                ans = Cmdaskbiphdemod(Cmd+2);
        } else if(cmdp == 'a' && cmdp2 == 'm'){
                ans = Cmdaskmandemod(Cmd+2);
        } else if(cmdp == 'a' && cmdp2 == 'r'){
                ans = Cmdaskrawdemod(Cmd+2);
        } else if(cmdp == 'n' && cmdp2 == 'r'){
                ans = CmdNRZrawDemod(Cmd+2);
        } else if(cmdp == 'p' && cmdp2 == '1'){
                ans = CmdPSK1rawDemod(Cmd+2);
        } else if(cmdp == 'p' && cmdp2 == '2'){
                ans = CmdPSK2rawDemod(Cmd+2);
        } else { 
                PrintAndLog("unknown modulation entered - see help ('h') for parameter structure");
        }
        return ans;
}

void setClockGrid(int clk, int offset) {
        if (offset > clk) offset %= clk;
        if (offset < 0) offset += clk;

        if (offset > GraphTraceLen || offset < 0) return;
        if (clk < 8 || clk > GraphTraceLen) {
                GridLocked = false;
                GridOffset = 0;
                PlotGridX = 0;
                PlotGridXdefault = 0;
                RepaintGraphWindow();
        } else {
                GridLocked = true;
                GridOffset = offset;
                PlotGridX = clk;
                PlotGridXdefault = clk;
                RepaintGraphWindow();
        }
}

int CmdGrid(const char *Cmd)
{
        sscanf(Cmd, "%i %i", &PlotGridX, &PlotGridY);
        PlotGridXdefault= PlotGridX;
        PlotGridYdefault= PlotGridY;
        RepaintGraphWindow();
        return 0;
}

int CmdSetGraphMarkers(const char *Cmd) {
        sscanf(Cmd, "%i %i", &CursorCPos, &CursorDPos);
        RepaintGraphWindow();
        return 0;
}

int CmdHexsamples(const char *Cmd)
{
        int i, j;
        int requested = 0;
        int offset = 0;
        char string_buf[25];
        char* string_ptr = string_buf;
        uint8_t got[BIGBUF_SIZE];

        sscanf(Cmd, "%i %i", &requested, &offset);

        /* if no args send something */
        if (requested == 0) {
                requested = 8;
        }
        if (offset + requested > sizeof(got)) {
                PrintAndLog("Tried to read past end of buffer, <bytes> + <offset> > %d", BIGBUF_SIZE);
                return 0;
        }

        GetFromBigBuf(got,requested,offset);
        WaitForResponse(CMD_ACK,NULL);

        i = 0;
        for (j = 0; j < requested; j++) {
                i++;
                string_ptr += sprintf(string_ptr, "%02x ", got[j]);
                if (i == 8) {
                        *(string_ptr - 1) = '\0';    // remove the trailing space
                        PrintAndLog("%s", string_buf);
                        string_buf[0] = '\0';
                        string_ptr = string_buf;
                        i = 0;
                }
                if (j == requested - 1 && string_buf[0] != '\0') { // print any remaining bytes
                        *(string_ptr - 1) = '\0';
                        PrintAndLog("%s", string_buf);
                        string_buf[0] = '\0';
                }
        }
        return 0;
}

int CmdHide(const char *Cmd)
{
        HideGraphWindow();
        return 0;
}

//zero mean GraphBuffer
int CmdHpf(const char *Cmd)
{
        int i;
        int accum = 0;

        for (i = 10; i < GraphTraceLen; ++i)
                accum += GraphBuffer[i];
        accum /= (GraphTraceLen - 10);
        for (i = 0; i < GraphTraceLen; ++i)
                GraphBuffer[i] -= accum;

        RepaintGraphWindow();
        return 0;
}

uint8_t getByte(uint8_t bits_per_sample, BitstreamIn* b)
{
        int i;
        uint8_t val = 0;
        for(i =0 ; i < bits_per_sample; i++)
        {
                val |= (headBit(b) << (7-i));
        }
        return val;
}

int getSamples(int n, bool silent)
{
        //If we get all but the last byte in bigbuf,
        // we don't have to worry about remaining trash
        // in the last byte in case the bits-per-sample
        // does not line up on byte boundaries

        uint8_t got[BIGBUF_SIZE-1] = { 0 };

        if (n == 0 || n > sizeof(got))
                n = sizeof(got);

        if (!silent) PrintAndLog("Reading %d bytes from device memory\n", n);
        GetFromBigBuf(got,n,0);
        if (!silent) PrintAndLog("Data fetched");
        UsbCommand response;
        WaitForResponse(CMD_ACK, &response);
        uint8_t bits_per_sample = 8;

        //Old devices without this feature would send 0 at arg[0]
        if(response.arg[0] > 0)
        {
                sample_config *sc = (sample_config *) response.d.asBytes;
                if (!silent) PrintAndLog("Samples @ %d bits/smpl, decimation 1:%d ", sc->bits_per_sample
                    , sc->decimation);
                bits_per_sample = sc->bits_per_sample;
        }
        if(bits_per_sample < 8)
        {
                if (!silent) PrintAndLog("Unpacking...");
                BitstreamIn bout = { got, bits_per_sample * n,  0};
                int j =0;
                for (j = 0; j * bits_per_sample < n * 8 && j < n; j++) {
                        uint8_t sample = getByte(bits_per_sample, &bout);
                        GraphBuffer[j] = ((int) sample )- 128;
                }
                GraphTraceLen = j;
                PrintAndLog("Unpacked %d samples" , j );
        }else
        {
                for (int j = 0; j < n; j++) {
                        GraphBuffer[j] = ((int)got[j]) - 128;
                }
                GraphTraceLen = n;
        }

        RepaintGraphWindow();
        return 0;
}

int CmdSamples(const char *Cmd)
{
        int n = strtol(Cmd, NULL, 0);
        return getSamples(n, false);
}

int CmdTuneSamples(const char *Cmd)
{
        int timeout = 0, arg = FLAG_TUNE_ALL;

        if(*Cmd == 'l') {
          arg = FLAG_TUNE_LF;
        } else if (*Cmd == 'h') {
          arg = FLAG_TUNE_HF;
        } else if (*Cmd != '\0') {
          PrintAndLog("use 'tune' or 'tune l' or 'tune h'");
          return 0;
        }

        printf("\nMeasuring antenna characteristics, please wait...");

        UsbCommand c = {CMD_MEASURE_ANTENNA_TUNING, {arg, 0, 0}};
        SendCommand(&c);

        UsbCommand resp;
        while(!WaitForResponseTimeout(CMD_MEASURED_ANTENNA_TUNING,&resp,1000)) {
                timeout++;
                printf(".");
                if (timeout > 7) {
                        PrintAndLog("\nNo response from Proxmark. Aborting...");
                        return 1;
                }
        }

        int peakv, peakf;
        int vLf125, vLf134, vHf;
        vLf125 = resp.arg[0] & 0xffff;
        vLf134 = resp.arg[0] >> 16;
        vHf = resp.arg[1] & 0xffff;;
        peakf = resp.arg[2] & 0xffff;
        peakv = resp.arg[2] >> 16;
        PrintAndLog("");
        PrintAndLog("# LF antenna: %5.2f V @   125.00 kHz", vLf125/1000.0);
        PrintAndLog("# LF antenna: %5.2f V @   134.00 kHz", vLf134/1000.0);
        PrintAndLog("# LF optimal: %5.2f V @%9.2f kHz", peakv/1000.0, 12000.0/(peakf+1));
        PrintAndLog("# HF antenna: %5.2f V @    13.56 MHz", vHf/1000.0);

 #define LF_UNUSABLE_V          2948            // was 2000. Changed due to bugfix in voltage measurements. LF results are now 47% higher.
 #define LF_MARGINAL_V          14739           // was 10000. Changed due to bugfix bug in voltage measurements. LF results are now 47% higher.
 #define HF_UNUSABLE_V          3167            // was 2000. Changed due to bugfix in voltage measurements. HF results are now 58% higher.
 #define HF_MARGINAL_V          7917            // was 5000. Changed due to bugfix in voltage measurements. HF results are now 58% higher.

        if (peakv < LF_UNUSABLE_V)
                PrintAndLog("# Your LF antenna is unusable.");
        else if (peakv < LF_MARGINAL_V)
                PrintAndLog("# Your LF antenna is marginal.");
        if (vHf < HF_UNUSABLE_V)
                PrintAndLog("# Your HF antenna is unusable.");
        else if (vHf < HF_MARGINAL_V)
                PrintAndLog("# Your HF antenna is marginal.");

        if (peakv >= LF_UNUSABLE_V)     {
                for (int i = 0; i < 256; i++) {
                        GraphBuffer[i] = resp.d.asBytes[i] - 128;
                }
                PrintAndLog("Displaying LF tuning graph. Divisor 89 is 134khz, 95 is 125khz.\n");
                PrintAndLog("\n");
                GraphTraceLen = 256;
                ShowGraphWindow();
                RepaintGraphWindow();
        }

        return 0;
}


int CmdLoad(const char *Cmd)
{
        char filename[FILE_PATH_SIZE] = {0x00};
        int len = 0;

        len = strlen(Cmd);
        if (len > FILE_PATH_SIZE) len = FILE_PATH_SIZE;
        memcpy(filename, Cmd, len);
        
        FILE *f = fopen(filename, "r");
        if (!f) {
                 PrintAndLog("couldn't open '%s'", filename);
                return 0;
        }

        GraphTraceLen = 0;
        char line[80];
        while (fgets(line, sizeof (line), f)) {
                GraphBuffer[GraphTraceLen] = atoi(line);
                GraphTraceLen++;
        }
        fclose(f);
        PrintAndLog("loaded %d samples", GraphTraceLen);
        RepaintGraphWindow();
        return 0;
}

int CmdLtrim(const char *Cmd)
{
        int ds = atoi(Cmd);
        if (GraphTraceLen<=0) return 0;
        for (int i = ds; i < GraphTraceLen; ++i)
                GraphBuffer[i-ds] = GraphBuffer[i];
        GraphTraceLen -= ds;

        RepaintGraphWindow();
        return 0;
}

// trim graph to input argument length
int CmdRtrim(const char *Cmd)
{
        int ds = atoi(Cmd);

        GraphTraceLen = ds;

        RepaintGraphWindow();
        return 0;
}

// trim graph (middle) piece
int CmdMtrim(const char *Cmd) {
        int start = 0, stop = 0;
        sscanf(Cmd, "%i %i", &start, &stop);

        if (start > GraphTraceLen       || stop > GraphTraceLen || start > stop) return 0;
        start++; //leave start position sample

        GraphTraceLen = stop - start;
        for (int i = 0; i < GraphTraceLen; i++) {
                GraphBuffer[i] = GraphBuffer[start+i];
        }
        return 0;
}


int CmdNorm(const char *Cmd)
{
        int i;
        int max = INT_MIN, min = INT_MAX;

        for (i = 10; i < GraphTraceLen; ++i) {
                if (GraphBuffer[i] > max)
                        max = GraphBuffer[i];
                if (GraphBuffer[i] < min)
                        min = GraphBuffer[i];
        }

        if (max != min) {
                for (i = 0; i < GraphTraceLen; ++i) {
                        GraphBuffer[i] = (GraphBuffer[i] - ((max + min) / 2)) * 256 /
                                (max - min);
                                //marshmelow: adjusted *1000 to *256 to make +/- 128 so demod commands still work
                }
        }
        RepaintGraphWindow();
        return 0;
}

int CmdPlot(const char *Cmd)
{
        ShowGraphWindow();
        return 0;
}

int CmdSave(const char *Cmd)
{
        char filename[FILE_PATH_SIZE] = {0x00};
        int len = 0;

        len = strlen(Cmd);
        if (len > FILE_PATH_SIZE) len = FILE_PATH_SIZE;
        memcpy(filename, Cmd, len);
         

        FILE *f = fopen(filename, "w");
        if(!f) {
                PrintAndLog("couldn't open '%s'", filename);
                return 0;
        }
        int i;
        for (i = 0; i < GraphTraceLen; i++) {
                fprintf(f, "%d\n", GraphBuffer[i]);
        }
        fclose(f);
        PrintAndLog("saved to '%s'", Cmd);
        return 0;
}

int CmdScale(const char *Cmd)
{
        CursorScaleFactor = atoi(Cmd);
        if (CursorScaleFactor == 0) {
                PrintAndLog("bad, can't have zero scale");
                CursorScaleFactor = 1;
        }
        RepaintGraphWindow();
        return 0;
}

int CmdDirectionalThreshold(const char *Cmd)
{
        int8_t upThres = param_get8(Cmd, 0);
        int8_t downThres = param_get8(Cmd, 1);

        printf("Applying Up Threshold: %d, Down Threshold: %d\n", upThres, downThres);

        int lastValue = GraphBuffer[0];
        GraphBuffer[0] = 0; // Will be changed at the end, but init 0 as we adjust to last samples value if no threshold kicks in.

        for (int i = 1; i < GraphTraceLen; ++i) {
                // Apply first threshold to samples heading up
                if (GraphBuffer[i] >= upThres && GraphBuffer[i] > lastValue)
                {
                        lastValue = GraphBuffer[i]; // Buffer last value as we overwrite it.
                        GraphBuffer[i] = 127;
                }
                // Apply second threshold to samples heading down
                else if (GraphBuffer[i] <= downThres && GraphBuffer[i] < lastValue)
                {
                        lastValue = GraphBuffer[i]; // Buffer last value as we overwrite it.
                        GraphBuffer[i] = -127;
                }
                else
                {
                        lastValue = GraphBuffer[i]; // Buffer last value as we overwrite it.
                        GraphBuffer[i] = GraphBuffer[i-1];

                }
        }
        GraphBuffer[0] = GraphBuffer[1]; // Aline with first edited sample.
        RepaintGraphWindow();
        return 0;
}

int CmdZerocrossings(const char *Cmd)
{
        // Zero-crossings aren't meaningful unless the signal is zero-mean.
        CmdHpf("");

        int sign = 1;
        int zc = 0;
        int lastZc = 0;

        for (int i = 0; i < GraphTraceLen; ++i) {
                if (GraphBuffer[i] * sign >= 0) {
                        // No change in sign, reproduce the previous sample count.
                        zc++;
                        GraphBuffer[i] = lastZc;
                } else {
                        // Change in sign, reset the sample count.
                        sign = -sign;
                        GraphBuffer[i] = lastZc;
                        if (sign > 0) {
                                lastZc = zc;
                                zc = 0;
                        }
                }
        }

        RepaintGraphWindow();
        return 0;
}

int usage_data_bin2hex(){
                PrintAndLog("Usage: data bin2hex <binary_digits>");
                PrintAndLog("       This function will ignore all characters not 1 or 0 (but stop reading on whitespace)");
                return 0;
}

/**
 * @brief Utility for conversion via cmdline.
 * @param Cmd
 * @return
 */
int Cmdbin2hex(const char *Cmd)
{
        int bg =0, en =0;
        if(param_getptr(Cmd, &bg, &en, 0))
        {
                return usage_data_bin2hex();
        }
        //Number of digits supplied as argument
        size_t length = en  - bg +1;
        size_t bytelen = (length+7) / 8;
        uint8_t* arr = (uint8_t *) malloc(bytelen);
        memset(arr, 0, bytelen);
        BitstreamOut bout = { arr, 0, 0 };

        for(; bg <= en ;bg++)
        {
                char c = Cmd[bg];
                if( c == '1')   pushBit(&bout, 1);
                else if( c == '0')      pushBit(&bout, 0);
                else PrintAndLog("Ignoring '%c'", c);
        }

        if(bout.numbits % 8 != 0)
        {
                printf("[padded with %d zeroes]\n", 8-(bout.numbits % 8));
        }

        //Uses printf instead of PrintAndLog since the latter
        // adds linebreaks to each printout - this way was more convenient since we don't have to
        // allocate a string and write to that first...
        for(size_t x = 0; x  < bytelen ; x++)
        {
                printf("%02X", arr[x]);
        }
        printf("\n");
        free(arr);
        return 0;
}

int usage_data_hex2bin() {
        PrintAndLog("Usage: data hex2bin <hex_digits>");
        PrintAndLog("       This function will ignore all non-hexadecimal characters (but stop reading on whitespace)");
        return 0;

}

int Cmdhex2bin(const char *Cmd)
{
        int bg =0, en =0;
        if(param_getptr(Cmd, &bg, &en, 0))
        {
                return usage_data_hex2bin();
        }


        while(bg <= en )
        {
                char x = Cmd[bg++];
                // capitalize
                if (x >= 'a' && x <= 'f')
                        x -= 32;
                // convert to numeric value
                if (x >= '0' && x <= '9')
                        x -= '0';
                else if (x >= 'A' && x <= 'F')
                        x -= 'A' - 10;
                else
                        continue;

                //Uses printf instead of PrintAndLog since the latter
                // adds linebreaks to each printout - this way was more convenient since we don't have to
                // allocate a string and write to that first...

                for(int i= 0 ; i < 4 ; ++i)
                        printf("%d",(x >> (3 - i)) & 1);
        }
        printf("\n");

        return 0;
}

static command_t CommandTable[] =
{
        {"help",            CmdHelp,            1, "This help"},
        {"askedgedetect",   CmdAskEdgeDetect,   1, "[threshold] Adjust Graph for manual ask demod using the length of sample differences to detect the edge of a wave (use 20-45, def:25)"},
        {"autocorr",        CmdAutoCorr,        1, "[window length] [g] -- Autocorrelation over window - g to save back to GraphBuffer (overwrite)"},
        {"biphaserawdecode",CmdBiphaseDecodeRaw,1, "[offset] [invert<0|1>] [maxErr] -- Biphase decode bin stream in DemodBuffer (offset = 0|1 bits to shift the decode start)"},
        {"bin2hex",         Cmdbin2hex,         1, "bin2hex <digits>     -- Converts binary to hexadecimal"},
        {"bitsamples",      CmdBitsamples,      0, "Get raw samples as bitstring"},
        {"buffclear",       CmdBuffClear,       1, "Clear sample buffer and graph window"},
        {"dec",             CmdDec,             1, "Decimate samples"},
        {"detectclock",     CmdDetectClockRate, 1, "[modulation] Detect clock rate of wave in GraphBuffer (options: 'a','f','n','p' for ask, fsk, nrz, psk respectively)"},
        {"getbitstream",    CmdGetBitStream,    1, "Convert GraphBuffer's >=1 values to 1 and <1 to 0"},
        {"grid",            CmdGrid,            1, "<x> <y> -- overlay grid on graph window, use zero value to turn off either"},
        {"hexsamples",      CmdHexsamples,      0, "<bytes> [<offset>] -- Dump big buffer as hex bytes"},
        {"hex2bin",         Cmdhex2bin,         1, "hex2bin <hexadecimal> -- Converts hexadecimal to binary"},
        {"hide",            CmdHide,            1, "Hide graph window"},
        {"hpf",             CmdHpf,             1, "Remove DC offset from trace"},
        {"load",            CmdLoad,            1, "<filename> -- Load trace (to graph window"},
        {"ltrim",           CmdLtrim,           1, "<samples> -- Trim samples from left of trace"},
        {"rtrim",           CmdRtrim,           1, "<location to end trace> -- Trim samples from right of trace"},
        {"mtrim",           CmdMtrim,           1, "<start> <stop> -- Trim out samples from the specified start to the specified stop"},
        {"manrawdecode",    Cmdmandecoderaw,    1, "[invert] [maxErr] -- Manchester decode binary stream in DemodBuffer"},
        {"norm",            CmdNorm,            1, "Normalize max/min to +/-128"},
        {"plot",            CmdPlot,            1, "Show graph window (hit 'h' in window for keystroke help)"},
        {"printdemodbuffer",CmdPrintDemodBuff,  1, "[x] [o] <offset> [l] <length> -- print the data in the DemodBuffer - 'x' for hex output"},
        {"rawdemod",        CmdRawDemod,        1, "[modulation] ... <options> -see help (h option) -- Demodulate the data in the GraphBuffer and output binary"},  
        {"samples",         CmdSamples,         0, "[512 - 40000] -- Get raw samples for graph window (GraphBuffer)"},
        {"save",            CmdSave,            1, "<filename> -- Save trace (from graph window)"},
        {"setgraphmarkers", CmdSetGraphMarkers, 1, "[orange_marker] [blue_marker] (in graph window)"},
        {"scale",           CmdScale,           1, "<int> -- Set cursor display scale"},
        {"setdebugmode",    CmdSetDebugMode,    1, "<0|1|2> -- Turn on or off Debugging Level for lf demods"},
        {"shiftgraphzero",  CmdGraphShiftZero,  1, "<shift> -- Shift 0 for Graphed wave + or - shift value"},
        {"dirthreshold",    CmdDirectionalThreshold,   1, "<thres up> <thres down> -- Max rising higher up-thres/ Min falling lower down-thres, keep rest as prev."},
        {"tune",            CmdTuneSamples,     0, "Get hw tune samples for graph window"},
        {"undec",           CmdUndec,           1, "Un-decimate samples by 2"},
        {"zerocrossings",   CmdZerocrossings,   1, "Count time between zero-crossings"},
        {NULL, NULL, 0, NULL}
};

int CmdData(const char *Cmd)
{
        CmdsParse(CommandTable, Cmd);
        return 0;
}

int CmdHelp(const char *Cmd)
{
        CmdsHelp(CommandTable);
        return 0;
}