Update lfops.c

[proxmark3-svn] / armsrc / lfops.c

diff --git a/armsrc/lfops.c b/armsrc/lfops.c
index 610781d240ed23dcad0fa6ca94c667ec8466aa9e..ed83df4823f9c35fc59b044440cfb27c1348e69b 100644 (file)
--- a/armsrc/lfops.c
+++ b/armsrc/lfops.c
@@ -4,7 +4,7 @@
 // the license.
 //-----------------------------------------------------------------------------
 // Miscellaneous routines for low frequency tag operations.
 // the license.
 //-----------------------------------------------------------------------------
 // Miscellaneous routines for low frequency tag operations.

-// Tags supported here so far are Texas Instruments (TI), HID
+// Tags supported here so far are Texas Instruments (TI), HID, EM4x05, EM410x

 // Also routines for raw mode reading/simulating of LF waveform
 //-----------------------------------------------------------------------------
 
 // Also routines for raw mode reading/simulating of LF waveform
 //-----------------------------------------------------------------------------
 


@@ -18,6 +18,7 @@
 #include "lfsampling.h"
 #include "protocols.h"
 #include "usb_cdc.h" // for usb_poll_validate_length
 #include "lfsampling.h"
 #include "protocols.h"
 #include "usb_cdc.h" // for usb_poll_validate_length

+#include "fpgaloader.h"

 
 /**
  * Function to do a modulation and then get samples.
 
 /**
  * Function to do a modulation and then get samples.


@@ -28,51 +29,103 @@
  */
 void ModThenAcquireRawAdcSamples125k(uint32_t delay_off, uint32_t period_0, uint32_t period_1, uint8_t *command)
 {
  */
 void ModThenAcquireRawAdcSamples125k(uint32_t delay_off, uint32_t period_0, uint32_t period_1, uint8_t *command)
 {

+       // start timer
+       StartTicks();

 
 

-       int divisor_used = 95; // 125 KHz
-       // see if 'h' was specified
+       // use lf config settings
+       sample_config *sc = getSamplingConfig();

 
 

-       if (command[strlen((char *) command) - 1] == 'h')
-               divisor_used = 88; // 134.8 KHz
-
-       sample_config sc = { 0,0,1, divisor_used, 0};
-       setSamplingConfig(&sc);
-       //clear read buffer
-       BigBuf_Clear_keep_EM();
-
-       /* Make sure the tag is reset */
+       // Make sure the tag is reset

        FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
        FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

-       SpinDelay(2500);
+       WaitMS(2500);

 
 

-       LFSetupFPGAForADC(sc.divisor, 1);
+       // clear read buffer (after fpga bitstream loaded...)
+       BigBuf_Clear_keep_EM();

 
 

-       // And a little more time for the tag to fully power up
-       SpinDelay(2000);
+       // power on
+       LFSetupFPGAForADC(sc->divisor, 1);

 
 

+       // And a little more time for the tag to fully power up
+       WaitMS(2000);
+       // if delay_off = 0 then just bitbang 1 = antenna on 0 = off for respective periods.
+       bool bitbang = delay_off == 0;

        // now modulate the reader field
        // now modulate the reader field

-       while(*command != '\0' && *command != ' ') {
+
+       if (bitbang) {
+               // HACK it appears the loop and if statements take up about 7us so adjust waits accordingly...
+               uint8_t hack_cnt = 7;
+               if (period_0 < hack_cnt || period_1 < hack_cnt) {
+                       DbpString("Warning periods cannot be less than 7us in bit bang mode");
+                       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+                       LED_D_OFF();
+                       return;
+               }
+
+               // hack2 needed---  it appears to take about 8-16us to turn the antenna back on 
+               // leading to ~ 1 to 2 125khz samples extra in every off period 
+               // so we should test for last 0 before next 1 and reduce period_0 by this extra amount...
+               // but is this time different for every antenna or other hw builds???  more testing needed
+
+               // prime cmd_len to save time comparing strings while modulating
+               int cmd_len = 0;
+               while(command[cmd_len] != '\0' && command[cmd_len] != ' ')
+                       cmd_len++;
+
+               int counter = 0;
+               bool off = false;
+               for (counter = 0; counter < cmd_len; counter++) {
+                       // if cmd = 0 then turn field off
+                       if (command[counter] == '0') {
+                               // if field already off leave alone (affects timing otherwise)
+                               if (off == false) {
+                                       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+                                       LED_D_OFF();
+                                       off = true;
+                               }
+                               // note we appear to take about 7us to switch over (or run the if statements/loop...)
+                               WaitUS(period_0-hack_cnt);
+                       // else if cmd = 1 then turn field on
+                       } else {
+                               // if field already on leave alone (affects timing otherwise)
+                               if (off) {
+                                       FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
+                                       LED_D_ON();
+                                       off = false;
+                               }
+                               // note we appear to take about 7us to switch over (or run the if statements/loop...)
+                               WaitUS(period_1-hack_cnt);
+                       }
+               }
+       } else { // old mode of cmd read using delay as off period
+               while(*command != '\0' && *command != ' ') {
+                       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+                       LED_D_OFF();
+                       WaitUS(delay_off);
+                       FpgaSendCommand(FPGA_CMD_SET_DIVISOR, sc->divisor);
+                       FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
+                       LED_D_ON();
+                       if(*(command++) == '0') {
+                               WaitUS(period_0);
+                       } else {
+                               WaitUS(period_1);
+                       }
+               }

                FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
                LED_D_OFF();
                FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
                LED_D_OFF();

-               SpinDelayUs(delay_off);
-               FpgaSendCommand(FPGA_CMD_SET_DIVISOR, sc.divisor);
-
-               FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
-               LED_D_ON();
-               if(*(command++) == '0')
-                       SpinDelayUs(period_0);
-               else
-                       SpinDelayUs(period_1);
+               WaitUS(delay_off);
+               FpgaSendCommand(FPGA_CMD_SET_DIVISOR, sc->divisor);

        }
        }

-       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-       LED_D_OFF();
-       SpinDelayUs(delay_off);
-       FpgaSendCommand(FPGA_CMD_SET_DIVISOR, sc.divisor);

 
        FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
 
        // now do the read
 
        FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
 
        // now do the read

-       DoAcquisition_config(false);
+       DoAcquisition_config(false, 0);
+
+       // Turn off antenna
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+       // tell client we are done
+       cmd_send(CMD_ACK,0,0,0,0,0);

 }
 
 /* blank r/w tag data stream
 }
 
 /* blank r/w tag data stream


@@ -387,7 +440,8 @@ void SimulateTagLowFrequency(int period, int gap, int ledcontrol)
        int i;
        uint8_t *tab = BigBuf_get_addr();
 
        int i;
        uint8_t *tab = BigBuf_get_addr();
 

-       FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
+       //note FpgaDownloadAndGo destroys the bigbuf so be sure this is called before now...
+       //FpgaDownloadAndGo(FPGA_BITSTREAM_LF);  

        FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_EDGE_DETECT);
 
        AT91C_BASE_PIOA->PIO_PER = GPIO_SSC_DOUT | GPIO_SSC_CLK;
        FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_EDGE_DETECT);
 
        AT91C_BASE_PIOA->PIO_PER = GPIO_SSC_DOUT | GPIO_SSC_CLK;


@@ -401,12 +455,19 @@ void SimulateTagLowFrequency(int period, int gap, int ledcontrol)
        i = 0;
        for(;;) {
                //wait until SSC_CLK goes HIGH
        i = 0;
        for(;;) {
                //wait until SSC_CLK goes HIGH

+               int ii = 0;

                while(!(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_CLK)) {
                while(!(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_CLK)) {

-                       if(BUTTON_PRESS() || (usb_poll_validate_length() )) {
-                               DbpString("Stopped");
-                               return;
+                       //only check every 1000th time (usb_poll_validate_length on some systems was too slow)
+                       if ( ii == 1000 ) {
+                               if (BUTTON_PRESS() || usb_poll_validate_length() ) {
+                                       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+                                       DbpString("Stopped");
+                                       return;
+                               }
+                               ii=0;

                        }
                        WDT_HIT();
                        }
                        WDT_HIT();

+                       ii++;

                }
                if (ledcontrol)
                        LED_D_ON();
                }
                if (ledcontrol)
                        LED_D_ON();


@@ -418,13 +479,20 @@ void SimulateTagLowFrequency(int period, int gap, int ledcontrol)
 
                if (ledcontrol)
                        LED_D_OFF();
 
                if (ledcontrol)
                        LED_D_OFF();

+               ii=0;

                //wait until SSC_CLK goes LOW
                while(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_CLK) {
                //wait until SSC_CLK goes LOW
                while(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_CLK) {

-                       if(BUTTON_PRESS()) {
-                               DbpString("Stopped");
-                               return;
+                       //only check every 1000th time (usb_poll_validate_length on some systems was too slow)
+                       if ( ii == 1000 ) { 
+                               if (BUTTON_PRESS() || usb_poll_validate_length() ) {
+                                       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+                                       DbpString("Stopped");
+                                       return;
+                               }
+                               ii=0;

                        }
                        WDT_HIT();
                        }
                        WDT_HIT();

+                       ii++;

                }
 
                i++;
                }
 
                i++;


@@ -436,6 +504,7 @@ void SimulateTagLowFrequency(int period, int gap, int ledcontrol)
                                SpinDelayUs(gap);
                        }
                }
                                SpinDelayUs(gap);
                        }
                }

+

        }
 }
 
        }
 }
 


@@ -500,7 +569,7 @@ static void fcAll(uint8_t fc, int *n, uint8_t clock, uint16_t *modCnt)
        uint8_t wavesPerClock = clock/fc;
        uint8_t mod = clock % fc;    //modifier
        uint8_t modAdj = fc/mod;     //how often to apply modifier
        uint8_t wavesPerClock = clock/fc;
        uint8_t mod = clock % fc;    //modifier
        uint8_t modAdj = fc/mod;     //how often to apply modifier

-       bool modAdjOk = !(fc % mod); //if (fc % mod==0) modAdjOk=TRUE;
+       bool modAdjOk = !(fc % mod); //if (fc % mod==0) modAdjOk=true;

        // loop through clock - step field clock
        for (uint8_t idx=0; idx < wavesPerClock; idx++){
                // put 1/2 FC length 1's and 1/2 0's per field clock wave (to create the wave)
        // loop through clock - step field clock
        for (uint8_t idx=0; idx < wavesPerClock; idx++){
                // put 1/2 FC length 1's and 1/2 0's per field clock wave (to create the wave)


@@ -525,7 +594,7 @@ static void fcAll(uint8_t fc, int *n, uint8_t clock, uint16_t *modCnt)
 
 // prepare a waveform pattern in the buffer based on the ID given then
 // simulate a HID tag until the button is pressed
 
 // prepare a waveform pattern in the buffer based on the ID given then
 // simulate a HID tag until the button is pressed

-void CmdHIDsimTAG(int hi, int lo, int ledcontrol)
+void CmdHIDsimTAG(int hi2, int hi, int lo, int ledcontrol)

 {
        int n=0, i=0;
        /*
 {
        int n=0, i=0;
        /*


@@ -538,10 +607,13 @@ void CmdHIDsimTAG(int hi, int lo, int ledcontrol)
         nor 1 bits, they are special patterns (a = set of 12 fc8 and b = set of 10 fc10)
        */
 
         nor 1 bits, they are special patterns (a = set of 12 fc8 and b = set of 10 fc10)
        */
 

-       if (hi>0xFFF) {
-               DbpString("Tags can only have 44 bits. - USE lf simfsk for larger tags");
+       if (hi2>0x0FFFFFFF) {
+               DbpString("Tags can only have 44 or 84 bits. - USE lf simfsk for larger tags");

                return;
        }
                return;
        }

+       // set LF so we don't kill the bigbuf we are setting with simulation data.
+       FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
+

        fc(0,&n);
        // special start of frame marker containing invalid bit sequences
        fc(8,  &n);     fc(8,  &n); // invalid
        fc(0,&n);
        // special start of frame marker containing invalid bit sequences
        fc(8,  &n);     fc(8,  &n); // invalid


@@ -550,13 +622,35 @@ void CmdHIDsimTAG(int hi, int lo, int ledcontrol)
        fc(8,  &n);     fc(10, &n); // logical 0
 
        WDT_HIT();
        fc(8,  &n);     fc(10, &n); // logical 0
 
        WDT_HIT();

-       // manchester encode bits 43 to 32
-       for (i=11; i>=0; i--) {
-               if ((i%4)==3) fc(0,&n);
-               if ((hi>>i)&1) {
-                       fc(10, &n); fc(8,  &n);         // low-high transition
-               } else {
-                       fc(8,  &n); fc(10, &n);         // high-low transition
+       if (hi2 > 0 || hi > 0xFFF){
+               // manchester encode bits 91 to 64 (91-84 are part of the header)
+               for (i=27; i>=0; i--) {
+                       if ((i%4)==3) fc(0,&n);
+                       if ((hi2>>i)&1) {
+                               fc(10, &n); fc(8,  &n);         // low-high transition
+                       } else {
+                               fc(8,  &n); fc(10, &n);         // high-low transition
+                       }
+               }
+               WDT_HIT();
+               // manchester encode bits 63 to 32
+               for (i=31; i>=0; i--) {
+                       if ((i%4)==3) fc(0,&n);
+                       if ((hi>>i)&1) {
+                               fc(10, &n); fc(8,  &n);         // low-high transition
+                       } else {
+                               fc(8,  &n); fc(10, &n);         // high-low transition
+                       }
+               }
+       } else {
+               // manchester encode bits 43 to 32
+               for (i=11; i>=0; i--) {
+                       if ((i%4)==3) fc(0,&n);
+                       if ((hi>>i)&1) {
+                               fc(10, &n); fc(8,  &n);         // low-high transition
+                       } else {
+                               fc(8,  &n); fc(10, &n);         // high-low transition
+                       }

                }
        }
 
                }
        }
 


@@ -592,6 +686,9 @@ void CmdFSKsimTAG(uint16_t arg1, uint16_t arg2, size_t size, uint8_t *BitStream)
        uint8_t clk = arg2 & 0xFF;
        uint8_t invert = (arg2 >> 8) & 1;
 
        uint8_t clk = arg2 & 0xFF;
        uint8_t invert = (arg2 >> 8) & 1;
 

+       // set LF so we don't kill the bigbuf we are setting with simulation data.
+       FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
+

        for (i=0; i<size; i++){
                if (BitStream[i] == invert){
                        fcAll(fcLow, &n, clk, &modCnt);
        for (i=0; i<size; i++){
                if (BitStream[i] == invert){
                        fcAll(fcLow, &n, clk, &modCnt);


@@ -645,6 +742,18 @@ static void biphaseSimBit(uint8_t c, int *n, uint8_t clock, uint8_t *phase)
        *n += clock;
 }
 
        *n += clock;
 }
 

+static void stAskSimBit(int *n, uint8_t clock) {
+       uint8_t *dest = BigBuf_get_addr();
+       uint8_t halfClk = clock/2;
+       //ST = .5 high .5 low 1.5 high .5 low 1 high    
+       memset(dest+(*n), 1, halfClk);
+       memset(dest+(*n) + halfClk, 0, halfClk);
+       memset(dest+(*n) + clock, 1, clock + halfClk);
+       memset(dest+(*n) + clock*2 + halfClk, 0, halfClk);
+       memset(dest+(*n) + clock*3, 1, clock);
+       *n += clock*4;
+}
+

 // args clock, ask/man or askraw, invert, transmission separator
 void CmdASKsimTag(uint16_t arg1, uint16_t arg2, size_t size, uint8_t *BitStream)
 {
 // args clock, ask/man or askraw, invert, transmission separator
 void CmdASKsimTag(uint16_t arg1, uint16_t arg2, size_t size, uint8_t *BitStream)
 {


@@ -655,6 +764,9 @@ void CmdASKsimTag(uint16_t arg1, uint16_t arg2, size_t size, uint8_t *BitStream)
        uint8_t separator = arg2 & 1;
        uint8_t invert = (arg2 >> 8) & 1;
 
        uint8_t separator = arg2 & 1;
        uint8_t invert = (arg2 >> 8) & 1;
 

+       // set LF so we don't kill the bigbuf we are setting with simulation data.
+       FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
+

        if (encoding==2){  //biphase
                uint8_t phase=0;
                for (i=0; i<size; i++){
        if (encoding==2){  //biphase
                uint8_t phase=0;
                for (i=0; i<size; i++){


@@ -669,14 +781,16 @@ void CmdASKsimTag(uint16_t arg1, uint16_t arg2, size_t size, uint8_t *BitStream)
                for (i=0; i<size; i++){
                        askSimBit(BitStream[i]^invert, &n, clk, encoding);
                }
                for (i=0; i<size; i++){
                        askSimBit(BitStream[i]^invert, &n, clk, encoding);
                }

-               if (encoding==0 && BitStream[0]==BitStream[size-1]){ //run a second set inverted (for biphase phase)
+               if (encoding==0 && BitStream[0]==BitStream[size-1]){ //run a second set inverted (for ask/raw || biphase phase)

                        for (i=0; i<size; i++){
                                askSimBit(BitStream[i]^invert^1, &n, clk, encoding);
                        }
                }
        }
                        for (i=0; i<size; i++){
                                askSimBit(BitStream[i]^invert^1, &n, clk, encoding);
                        }
                }
        }

-       
-       if (separator==1) Dbprintf("sorry but separator option not yet available"); 
+       if (separator==1 && encoding == 1)
+               stAskSimBit(&n, clk);
+       else if (separator==1)
+               Dbprintf("sorry but separator option not yet available");

 
        Dbprintf("Simulating with clk: %d, invert: %d, encoding: %d, separator: %d, n: %d",clk, invert, encoding, separator, n);
        //DEBUG
 
        Dbprintf("Simulating with clk: %d, invert: %d, encoding: %d, separator: %d, n: %d",clk, invert, encoding, separator, n);
        //DEBUG


@@ -724,11 +838,14 @@ void CmdPSKsimTag(uint16_t arg1, uint16_t arg2, size_t size, uint8_t *BitStream)
        uint8_t carrier = arg1 & 0xFF;
        uint8_t invert = arg2 & 0xFF;
        uint8_t curPhase = 0;
        uint8_t carrier = arg1 & 0xFF;
        uint8_t invert = arg2 & 0xFF;
        uint8_t curPhase = 0;

+       // set LF so we don't kill the bigbuf we are setting with simulation data.
+       FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
+

        for (i=0; i<size; i++){
                if (BitStream[i] == curPhase){
        for (i=0; i<size; i++){
                if (BitStream[i] == curPhase){

-                       pskSimBit(carrier, &n, clk, &curPhase, FALSE);
+                       pskSimBit(carrier, &n, clk, &curPhase, false);

                } else {
                } else {

-                       pskSimBit(carrier, &n, clk, &curPhase, TRUE);
+                       pskSimBit(carrier, &n, clk, &curPhase, true);

                }
        }
        Dbprintf("Simulating with Carrier: %d, clk: %d, invert: %d, n: %d",carrier, clk, invert, n);
                }
        }
        Dbprintf("Simulating with Carrier: %d, clk: %d, invert: %d, n: %d",carrier, clk, invert, n);


@@ -745,13 +862,14 @@ void CmdPSKsimTag(uint16_t arg1, uint16_t arg2, size_t size, uint8_t *BitStream)
 }
 
 // loop to get raw HID waveform then FSK demodulate the TAG ID from it
 }
 
 // loop to get raw HID waveform then FSK demodulate the TAG ID from it

-void CmdHIDdemodFSK(int findone, int *high, int *low, int ledcontrol)
+void CmdHIDdemodFSK(int findone, int *high2, int *high, int *low, int ledcontrol)

 {
        uint8_t *dest = BigBuf_get_addr();
        //const size_t sizeOfBigBuff = BigBuf_max_traceLen();
        size_t size; 
        uint32_t hi2=0, hi=0, lo=0;
        int idx=0;
 {
        uint8_t *dest = BigBuf_get_addr();
        //const size_t sizeOfBigBuff = BigBuf_max_traceLen();
        size_t size; 
        uint32_t hi2=0, hi=0, lo=0;
        int idx=0;

+       int dummyIdx = 0;

        // Configure to go in 125Khz listen mode
        LFSetupFPGAForADC(95, true);
 
        // Configure to go in 125Khz listen mode
        LFSetupFPGAForADC(95, true);
 


@@ -759,7 +877,6 @@ void CmdHIDdemodFSK(int findone, int *high, int *low, int ledcontrol)
        BigBuf_Clear_keep_EM();
 
        while(!BUTTON_PRESS() && !usb_poll_validate_length()) {
        BigBuf_Clear_keep_EM();
 
        while(!BUTTON_PRESS() && !usb_poll_validate_length()) {

-

                WDT_HIT();
                if (ledcontrol) LED_A_ON();
 
                WDT_HIT();
                if (ledcontrol) LED_A_ON();
 


@@ -767,72 +884,84 @@ void CmdHIDdemodFSK(int findone, int *high, int *low, int ledcontrol)
                // FSK demodulator
                //size = sizeOfBigBuff;  //variable size will change after demod so re initialize it before use
                size = 50*128*2; //big enough to catch 2 sequences of largest format
                // FSK demodulator
                //size = sizeOfBigBuff;  //variable size will change after demod so re initialize it before use
                size = 50*128*2; //big enough to catch 2 sequences of largest format

-               idx = HIDdemodFSK(dest, &size, &hi2, &hi, &lo);
+               idx = HIDdemodFSK(dest, &size, &hi2, &hi, &lo, &dummyIdx);

                
                if (idx>0 && lo>0 && (size==96 || size==192)){
                
                if (idx>0 && lo>0 && (size==96 || size==192)){

+                       uint8_t bitlen = 0;
+                       uint32_t fc = 0;
+                       uint32_t cardnum = 0;
+                       bool decoded = false;
+

                        // go over previously decoded manchester data and decode into usable tag ID
                        // go over previously decoded manchester data and decode into usable tag ID

-                       if (hi2 != 0){ //extra large HID tags  88/192 bits
-                               Dbprintf("TAG ID: %x%08x%08x (%d)",
-                                 (unsigned int) hi2, (unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF);
-                       }else {  //standard HID tags 44/96 bits
-                               //Dbprintf("TAG ID: %x%08x (%d)",(unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF); //old print cmd
-                               uint8_t bitlen = 0;
-                               uint32_t fc = 0;
-                               uint32_t cardnum = 0;
-                               if (((hi>>5)&1) == 1){//if bit 38 is set then < 37 bit format is used
-                                       uint32_t lo2=0;
-                                       lo2=(((hi & 31) << 12) | (lo>>20)); //get bits 21-37 to check for format len bit
-                                       uint8_t idx3 = 1;
-                                       while(lo2 > 1){ //find last bit set to 1 (format len bit)
-                                               lo2=lo2 >> 1;
-                                               idx3++;
-                                       }
-                                       bitlen = idx3+19;
-                                       fc =0;
-                                       cardnum=0;
-                                       if(bitlen == 26){
-                                               cardnum = (lo>>1)&0xFFFF;
-                                               fc = (lo>>17)&0xFF;
-                                       }
-                                       if(bitlen == 37){
-                                               cardnum = (lo>>1)&0x7FFFF;
-                                               fc = ((hi&0xF)<<12)|(lo>>20);
-                                       }
-                                       if(bitlen == 34){
-                                               cardnum = (lo>>1)&0xFFFF;
-                                               fc= ((hi&1)<<15)|(lo>>17);
-                                       }
-                                       if(bitlen == 35){
-                                               cardnum = (lo>>1)&0xFFFFF;
-                                               fc = ((hi&1)<<11)|(lo>>21);
-                                       }
+                       if ((hi2 & 0x000FFFF) != 0){ //extra large HID tags  88/192 bits
+                               uint32_t bp = hi2 & 0x000FFFFF;
+                               bitlen = 63;
+                               while (bp > 0) {
+                                       bp = bp >> 1;
+                                       bitlen++;

                                }
                                }

-                               else { //if bit 38 is not set then 37 bit format is used
-                                       bitlen= 37;
-                                       fc =0;
-                                       cardnum=0;
-                                       if(bitlen==37){
-                                               cardnum = (lo>>1)&0x7FFFF;
-                                               fc = ((hi&0xF)<<12)|(lo>>20);
-                                       }
+                       } else if ((hi >> 6) > 0) {
+                               uint32_t bp = hi;
+                               bitlen = 31;
+                               while (bp > 0) {
+                                       bp = bp >> 1;
+                                       bitlen++;

                                }
                                }

-                               //Dbprintf("TAG ID: %x%08x (%d)",
-                               // (unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF);
-                               Dbprintf("TAG ID: %x%08x (%d) - Format Len: %dbit - FC: %d - Card: %d",
-                                                (unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF,
-                                                (unsigned int) bitlen, (unsigned int) fc, (unsigned int) cardnum);
+                       } else if (((hi >> 5) & 1) == 0) {
+                               bitlen = 37;
+                       } else if ((hi & 0x0000001F) > 0 ) {
+                               uint32_t bp = (hi & 0x0000001F);
+                               bitlen = 31;
+                               while (bp > 0) {
+                                       bp = bp >> 1;
+                                       bitlen++;
+                               }
+                       } else {
+                               uint32_t bp = lo;
+                               bitlen = 0;
+                               while (bp > 0) {
+                                       bp = bp >> 1;
+                                       bitlen++;
+                               }
+                       }
+                       switch (bitlen){
+                               case 26:
+                                       cardnum = (lo>>1)&0xFFFF;
+                                       fc = (lo>>17)&0xFF;
+                                       decoded = true;
+                                       break;
+                               case 35:
+                                       cardnum = (lo>>1)&0xFFFFF;
+                                       fc = ((hi&1)<<11)|(lo>>21);
+                                       decoded = true;
+                                       break;

                        }
                        }

+                               
+                       if (hi2 != 0) //extra large HID tags  88/192 bits
+                               Dbprintf("TAG ID: %x%08x%08x (%d)",
+                                       (unsigned int) hi2, (unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF);
+                       else 
+                               Dbprintf("TAG ID: %x%08x (%d)",
+                                       (unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF);
+                       
+                       if (decoded)
+                               Dbprintf("Format Len: %dbits - FC: %d - Card: %d",
+                                       (unsigned int) bitlen, (unsigned int) fc, (unsigned int) cardnum);
+

                        if (findone){
                                if (ledcontrol) LED_A_OFF();
                        if (findone){
                                if (ledcontrol) LED_A_OFF();

+                               *high2 = hi2;

                                *high = hi;
                                *low = lo;
                                *high = hi;
                                *low = lo;

-                               return;
+                               break;

                        }
                        // reset
                }
                hi2 = hi = lo = idx = 0;
                WDT_HIT();
        }
                        }
                        // reset
                }
                hi2 = hi = lo = idx = 0;
                WDT_HIT();
        }

+
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

        DbpString("Stopped");
        if (ledcontrol) LED_A_OFF();
 }
        DbpString("Stopped");
        if (ledcontrol) LED_A_OFF();
 }


@@ -842,7 +971,7 @@ void CmdAWIDdemodFSK(int findone, int *high, int *low, int ledcontrol)
 {
        uint8_t *dest = BigBuf_get_addr();
        size_t size; 
 {
        uint8_t *dest = BigBuf_get_addr();
        size_t size; 

-       int idx=0;
+       int idx=0, dummyIdx=0;

        //clear read buffer
        BigBuf_Clear_keep_EM();
        // Configure to go in 125Khz listen mode
        //clear read buffer
        BigBuf_Clear_keep_EM();
        // Configure to go in 125Khz listen mode


@@ -856,7 +985,7 @@ void CmdAWIDdemodFSK(int findone, int *high, int *low, int ledcontrol)
                DoAcquisition_default(-1,true);
                // FSK demodulator
                size = 50*128*2; //big enough to catch 2 sequences of largest format
                DoAcquisition_default(-1,true);
                // FSK demodulator
                size = 50*128*2; //big enough to catch 2 sequences of largest format

-               idx = AWIDdemodFSK(dest, &size);
+               idx = AWIDdemodFSK(dest, &size, &dummyIdx);

                
                if (idx<=0 || size!=96) continue;
                // Index map
                
                if (idx<=0 || size!=96) continue;
                // Index map


@@ -917,12 +1046,13 @@ void CmdAWIDdemodFSK(int findone, int *high, int *low, int ledcontrol)
                }
                if (findone){
                        if (ledcontrol) LED_A_OFF();
                }
                if (findone){
                        if (ledcontrol) LED_A_OFF();

-                       return;
+                       break;

                }
                // reset
                idx = 0;
                WDT_HIT();
        }
                }
                // reset
                idx = 0;
                WDT_HIT();
        }

+       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

        DbpString("Stopped");
        if (ledcontrol) LED_A_OFF();
 }
        DbpString("Stopped");
        if (ledcontrol) LED_A_OFF();
 }


@@ -977,13 +1107,14 @@ void CmdEM410xdemod(int findone, int *high, int *low, int ledcontrol)
                                if (ledcontrol) LED_A_OFF();
                                *high=lo>>32;
                                *low=lo & 0xFFFFFFFF;
                                if (ledcontrol) LED_A_OFF();
                                *high=lo>>32;
                                *low=lo & 0xFFFFFFFF;

-                               return;
+                               break;

                        }
                }
                WDT_HIT();
                hi = lo = size = idx = 0;
                clk = invert = errCnt = 0;
        }
                        }
                }
                WDT_HIT();
                hi = lo = size = idx = 0;
                clk = invert = errCnt = 0;
        }

+       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

        DbpString("Stopped");
        if (ledcontrol) LED_A_OFF();
 }
        DbpString("Stopped");
        if (ledcontrol) LED_A_OFF();
 }


@@ -996,6 +1127,7 @@ void CmdIOdemodFSK(int findone, int *high, int *low, int ledcontrol)
        uint8_t version=0;
        uint8_t facilitycode=0;
        uint16_t number=0;
        uint8_t version=0;
        uint8_t facilitycode=0;
        uint16_t number=0;

+       int dummyIdx=0;

        //clear read buffer
        BigBuf_Clear_keep_EM();
        // Configure to go in 125Khz listen mode
        //clear read buffer
        BigBuf_Clear_keep_EM();
        // Configure to go in 125Khz listen mode


@@ -1007,7 +1139,7 @@ void CmdIOdemodFSK(int findone, int *high, int *low, int ledcontrol)
                DoAcquisition_default(-1,true);
                //fskdemod and get start index
                WDT_HIT();
                DoAcquisition_default(-1,true);
                //fskdemod and get start index
                WDT_HIT();

-               idx = IOdemodFSK(dest, BigBuf_max_traceLen());
+               idx = IOdemodFSK(dest, BigBuf_max_traceLen(), &dummyIdx);

                if (idx<0) continue;
                //valid tag found
 
                if (idx<0) continue;
                //valid tag found
 


@@ -1042,7 +1174,7 @@ void CmdIOdemodFSK(int findone, int *high, int *low, int ledcontrol)
                        //LED_A_OFF();
                        *high=code;
                        *low=code2;
                        //LED_A_OFF();
                        *high=code;
                        *low=code2;

-                       return;
+                       break;

                }
                code=code2=0;
                version=facilitycode=0;
                }
                code=code2=0;
                version=facilitycode=0;


@@ -1051,6 +1183,7 @@ void CmdIOdemodFSK(int findone, int *high, int *low, int ledcontrol)
 
                WDT_HIT();
        }
 
                WDT_HIT();
        }

+       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

        DbpString("Stopped");
        if (ledcontrol) LED_A_OFF();
 }
        DbpString("Stopped");
        if (ledcontrol) LED_A_OFF();
 }


@@ -1065,50 +1198,262 @@ void CmdIOdemodFSK(int findone, int *high, int *low, int ledcontrol)
  * and enlarge the gap ones.
  * Q5 tags seems to have issues when these values changes. 
  */
  * and enlarge the gap ones.
  * Q5 tags seems to have issues when these values changes. 
  */

+
+ /*
+ // Original Timings for reference
+//note startgap must be sent after tag has been powered up for more than 3ms (per T5557 ds)
+ 

 #define START_GAP 31*8 // was 250 // SPEC:  1*8 to 50*8 - typ 15*8 (or 15fc)
 #define WRITE_GAP 20*8 // was 160 // SPEC:  1*8 to 20*8 - typ 10*8 (or 10fc)
 #define WRITE_0   18*8 // was 144 // SPEC: 16*8 to 32*8 - typ 24*8 (or 24fc)
 #define WRITE_1   50*8 // was 400 // SPEC: 48*8 to 64*8 - typ 56*8 (or 56fc)  432 for T55x7; 448 for E5550
 #define READ_GAP  15*8 
 
 #define START_GAP 31*8 // was 250 // SPEC:  1*8 to 50*8 - typ 15*8 (or 15fc)
 #define WRITE_GAP 20*8 // was 160 // SPEC:  1*8 to 20*8 - typ 10*8 (or 10fc)
 #define WRITE_0   18*8 // was 144 // SPEC: 16*8 to 32*8 - typ 24*8 (or 24fc)
 #define WRITE_1   50*8 // was 400 // SPEC: 48*8 to 64*8 - typ 56*8 (or 56fc)  432 for T55x7; 448 for E5550
 #define READ_GAP  15*8 
 

+*/
+/* Q5 timing datasheet:
+ * Type                  |  MIN   | Typical |  Max   |
+ * Start_Gap             |  10*8  |    ?    |  50*8  |
+ * Write_Gap Normal mode |   8*8  |   14*8  |  20*8  | 
+ * Write_Gap Fast Mode   |   8*8  |    ?    |  20*8  |
+ * Write_0   Normal mode |  16*8  |   24*8  |  32*8  |
+ * Write_1   Normal mode |  48*8  |   56*8  |  64*8  |
+ * Write_0   Fast Mode   |   8*8  |   12*8  |  16*8  |
+ * Write_1   Fast Mode   |  24*8  |   28*8  |  32*8  |
+*/
+
+/* T5557 timing datasheet:
+ * Type                  |  MIN   | Typical |  Max   |
+ * Start_Gap             |  10*8  |    ?    |  50*8  |
+ * Write_Gap Normal mode |   8*8  |50-150us |  30*8  | 
+ * Write_Gap Fast Mode   |   8*8  |    ?    |  20*8  |
+ * Write_0   Normal mode |  16*8  |   24*8  |  31*8  | 
+ * Write_1   Normal mode |  48*8  |   54*8  |  63*8  | 
+ * Write_0   Fast Mode   |   8*8  |   12*8  |  15*8  |
+ * Write_1   Fast Mode   |  24*8  |   28*8  |  31*8  |
+*/
+
+/* T5577C timing datasheet for Fixed-Bit-Length protocol (defualt):
+ * Type                  |  MIN   | Typical |  Max   |
+ * Start_Gap             |   8*8  |   15*8  |  50*8  |
+ * Write_Gap Normal mode |   8*8  |   10*8  |  20*8  | 
+ * Write_Gap Fast Mode   |   8*8  |   10*8  |  20*8  |
+ * Write_0   Normal mode |  16*8  |   24*8  |  32*8  | 
+ * Write_1   Normal mode |  48*8  |   56*8  |  64*8  | 
+ * Write_0   Fast Mode   |   8*8  |   12*8  |  16*8  |
+ * Write_1   Fast Mode   |  24*8  |   28*8  |  32*8  |
+*/
+
+// Structure to hold Timing values.  In future will be simplier to add user changable timings.
+typedef struct  {
+       uint16_t  START_GAP;
+       uint16_t  WRITE_GAP;
+       uint16_t  WRITE_0;
+       uint16_t  WRITE_1;
+       uint16_t  WRITE_2;
+       uint16_t  WRITE_3;
+       uint16_t  READ_GAP;
+} T55xx_Timing;
+
+// Set Initial/Default Values.  Note: *8 can occure when used.  This should keep things simplier here.
+T55xx_Timing T55xx_Timing_FixedBit = { 31 * 8   , 20 * 8   , 18 * 8 , 50 * 8 , 0      , 0      , 15 * 8   };
+T55xx_Timing T55xx_Timing_LLR      = { 31 * 8   , 20 * 8   , 18 * 8 , 50 * 8 , 0      , 0      , 15 * 8   };
+T55xx_Timing T55xx_Timing_Leading0 = { 31 * 8   , 20 * 8   , 18 * 8 , 40 * 8 , 0      , 0      , 15 * 8   };
+T55xx_Timing T55xx_Timing_1of4     = { 31 * 8   , 20 * 8   , 18 * 8 , 34 * 8 , 50 * 8 , 66 * 8 , 15 * 8   };
+
+// Some defines for readability
+#define T55xx_DLMode_Fixed         0 // Default Mode
+#define T55xx_DLMode_LLR           1 // Long Leading Reference
+#define T55xx_DLMode_Leading0      2 // Leading Zero
+#define T55xx_DLMode_1of4                 3 // 1 of 4
+#define T55xx_LongLeadingReference 4 // Value to tell Write Bit to send long reference
+// Macro for code readability
+#define BitStream_Byte(X) ((X) >> 3)
+#define BitStream_Bit(X)  ((X) &  7)  
+
+

 void TurnReadLFOn(int delay) {
        FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
        // Give it a bit of time for the resonant antenna to settle.
 void TurnReadLFOn(int delay) {
        FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
        // Give it a bit of time for the resonant antenna to settle.

-       SpinDelayUs(delay); //155*8 //50*8
+       WaitUS(delay); //155*8 //50*8

 }
 
 // Write one bit to card
 }
 
 // Write one bit to card

-void T55xxWriteBit(int bit) {
-       if (!bit)
-               TurnReadLFOn(WRITE_0);
-       else
-               TurnReadLFOn(WRITE_1);
+void T55xxWriteBit(int bit, T55xx_Timing *Timings) {
+
+       // If bit = 4 Send Long Leading Reference which is 138 + WRITE_0        
+   // Dbprintf ("Bits : %d",bit);
+       switch (bit){
+               case 0 : TurnReadLFOn(Timings->WRITE_0);             break; // Send bit  0/00
+               case 1 : TurnReadLFOn(Timings->WRITE_1);             break; // Send bit  1/01
+               case 2 : TurnReadLFOn(Timings->WRITE_2);             break; // Send bits   10
+               case 3 : TurnReadLFOn(Timings->WRITE_3);                     break; // Send bits   11
+               case 4 : TurnReadLFOn(Timings->WRITE_0 + (136 * 8)); break; // Send Long Leading Reference 
+       }               

        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

-       SpinDelayUs(WRITE_GAP);
+       WaitUS(Timings->WRITE_GAP);

 }
 
 }
 

-// Send T5577 reset command then read stream (see if we can identify the start of the stream)
-void T55xxResetRead(void) {
-       LED_A_ON();
-       //clear buffer now so it does not interfere with timing later
-       BigBuf_Clear_keep_EM();
+// Function to abstract an Arbitrary length byte array to store bit pattern.
+// bit_array    - Array to hold data/bit pattern
+// start_offset - bit location to start storing new bits.
+// data         - upto 32 bits of data to store
+// num_bits     - how many bits (low x bits of data)  Max 32 bits at a time
+// max_len         - how many bytes can the bit_array hold (ensure no buffer overflow)
+// returns "Next" bit offset / bits stored (for next store)
+//int T55xx_SetBits (uint8_t *bit_array, int start_offset, uint32_t data      , int num_bits, int max_len)
+int T55xx_SetBits (uint8_t *BitStream, uint8_t start_offset, uint32_t data , uint8_t num_bits, uint8_t max_len)
+{
+    int8_t offset;                   
+    int8_t NextOffset = start_offset;
+
+    // Check if data will fit.
+    if ((start_offset + num_bits) <= (max_len*8)) {
+       // Loop through the data and store                          
+        for (offset = (num_bits-1); offset >= 0; offset--) {
+
+            if ((data >> offset) & 1)  BitStream[BitStream_Byte(NextOffset)] |= (1         << BitStream_Bit(NextOffset));     // Set the bit to 1
+            else                       BitStream[BitStream_Byte(NextOffset)] &= (0xff ^ (1 << BitStream_Bit(NextOffset)));    // Set the bit to 0
+
+            NextOffset++;                                
+        }
+       }
+       else{
+        // Note: This should never happen unless some code changes cause it.  
+        // So short message for coders when testing.
+        Dbprintf ("T55 too many bits"); 
+    }
+    return NextOffset;          
+}

 
 

+// Send one downlink command to the card 
+void T55xx_SendCMD (uint32_t Data, uint32_t Block, uint32_t Pwd, uint8_t arg) { 
+       
+       /*
+               arg bits
+               xxxxxxx1 0x01 PwdMode
+               xxxxxx1x 0x02 Page
+               xxxxx1xx 0x04 testMode
+               xxx11xxx 0x18 downlink mode
+               xx1xxxxx 0x20 !reg_readmode
+               x1xxxxxx 0x40 called for a read, so no data packet
+               1xxxxxxx 0x80 reset
+        
+       */
+       bool    PwdMode                 = ((arg & 0x01) == 0x01);
+       bool    Page                    =  (arg & 0x02);
+       bool    testMode                = ((arg & 0x04) == 0x04);
+       uint8_t downlink_mode   =  (arg >> 3) & 0x03;
+       bool    reg_readmode    = ((arg & 0x20) == 0x20);
+       bool    read_cmd                = ((arg & 0x40) == 0x40);
+    bool    reset           =  (arg & 0x80);
+    
+    uint8_t i = 0;             
+       uint8_t BitStream[10];  // Max Downlink Command size ~74 bits, so 10 bytes (80 bits)
+       uint8_t BitStreamLen;
+       T55xx_Timing *Timing;
+       uint8_t SendBits;
+       
+       // Assigning Downlink Timeing for write
+       switch (downlink_mode)
+       {
+               case T55xx_DLMode_Fixed    : Timing = &T55xx_Timing_FixedBit;  break; 
+               case T55xx_DLMode_LLR      : Timing = &T55xx_Timing_LLR;           break;
+               case T55xx_DLMode_Leading0 : Timing = &T55xx_Timing_Leading0;  break;
+               case T55xx_DLMode_1of4     : Timing = &T55xx_Timing_1of4;      break;
+               default:
+                               Timing = &T55xx_Timing_FixedBit;
+       }       
+
+       // Build Bit Stream to send.
+       memset (BitStream,0x00,sizeof(BitStream));
+       
+       BitStreamLen = 0; // Ensure 0 bit index to start.
+       
+       // Add Leading 0 and 1 of 4 reference bit
+       if ((downlink_mode == T55xx_DLMode_Leading0) || (downlink_mode == T55xx_DLMode_1of4))  
+               BitStreamLen = T55xx_SetBits (BitStream, BitStreamLen, 0, 1,sizeof(BitStream)); 
+
+       // Add extra reference 0 for 1 of 4
+       if (downlink_mode == T55xx_DLMode_1of4)                            
+               BitStreamLen = T55xx_SetBits (BitStream, BitStreamLen, 0, 1,sizeof(BitStream)); 
+
+       // Add Opcode 
+    if (reset) {
+        //  Reset : r*) 00
+            BitStreamLen = T55xx_SetBits (BitStream, BitStreamLen, 0, 2,sizeof(BitStream)); 
+    }
+    else
+    {
+        if (testMode) Dbprintf("TestMODE");
+        BitStreamLen = T55xx_SetBits (BitStream, BitStreamLen,testMode ? 0 : 1    , 1,sizeof(BitStream));      
+        BitStreamLen = T55xx_SetBits (BitStream, BitStreamLen,testMode ? 1 : Page , 1,sizeof(BitStream));      
+       
+        if (PwdMode) {
+            // Leading 0 and 1 of 4 00 fixed bits if passsword used            
+            if ((downlink_mode == T55xx_DLMode_Leading0) || (downlink_mode == T55xx_DLMode_1of4)) {
+                BitStreamLen = T55xx_SetBits (BitStream, BitStreamLen, 0, 2,sizeof(BitStream)); 
+            }
+            BitStreamLen = T55xx_SetBits (BitStream, BitStreamLen, Pwd, 32,sizeof(BitStream)); 
+        }
+
+        // Add Lock bit 0
+        if (!reg_readmode) BitStreamLen = T55xx_SetBits (BitStream, BitStreamLen, 0, 1,sizeof(BitStream)); 
+
+        // Add Data if a write command
+        if (!read_cmd) BitStreamLen = T55xx_SetBits (BitStream, BitStreamLen, Data, 32,sizeof(BitStream)); 
+
+        // Add Address
+        if (!reg_readmode) BitStreamLen = T55xx_SetBits (BitStream, BitStreamLen, Block, 3,sizeof(BitStream)); 
+    }
+    
+       // Send Bits to T55xx

        // Set up FPGA, 125kHz
        LFSetupFPGAForADC(95, true);
        // Set up FPGA, 125kHz
        LFSetupFPGAForADC(95, true);

-
+       StartTicks();
+       // make sure tag is fully powered up...
+       WaitMS(5);

        // Trigger T55x7 in mode.
        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
        // Trigger T55x7 in mode.
        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

-       SpinDelayUs(START_GAP);
+       WaitUS(Timing->START_GAP);

 
 

-       // reset tag - op code 00
-       T55xxWriteBit(0);
-       T55xxWriteBit(0);
+       // If long leading 0 send long reference pulse
+       if (downlink_mode ==  T55xx_DLMode_LLR) 
+               T55xxWriteBit (T55xx_LongLeadingReference,Timing); // Send Long Leading Start Reference

 
 

-       // Turn field on to read the response
-       TurnReadLFOn(READ_GAP);
+   if ((downlink_mode ==  T55xx_DLMode_1of4) && (BitStreamLen > 0)) { // 1 of 4 need to send 2 bits at a time
+               for ( i = 0; i < BitStreamLen-1; i+=2 ) {
+                       SendBits  = (BitStream[BitStream_Byte(i  )] >> (BitStream_Bit(i  )) & 1) << 1;   // Bit i
+            SendBits += (BitStream[BitStream_Byte(i+1)] >> (BitStream_Bit(i+1)) & 1);        // Bit i+1; 
+                       T55xxWriteBit (SendBits & 3,Timing);
+               }
+       }
+       else {
+               for (i = 0; i < BitStreamLen; i++) {
+                       SendBits = (BitStream[BitStream_Byte(i)] >> BitStream_Bit(i)); 
+                       T55xxWriteBit (SendBits & 1,Timing);
+       }               
+       }
+}
+
+// Send T5577 reset command then read stream (see if we can identify the start of the stream)
+void T55xxResetRead(void) {
+       LED_A_ON();
+
+    //  send  r* 00 
+    uint8_t arg = 0x80;  // SendCMD will add correct reference mode based on flags (when added).
+
+    // Add in downlink_mode when ready
+    //    arg |= 0x00;  // dlmode << 3  (00 default - 08 leading 0 - 10 Fixed - 18 1 of 4 )
+
+       //clear buffer now so it does not interfere with timing later
+       BigBuf_Clear_keep_EM();
+
+       T55xx_SendCMD (0, 0, 0, arg); //, true);
+
+       TurnReadLFOn(T55xx_Timing_FixedBit.READ_GAP);

 
        // Acquisition
 
        // Acquisition

-       doT55x7Acquisition(BigBuf_max_traceLen());
+       DoPartialAcquisition(0, true, BigBuf_max_traceLen(), 0);

 
        // Turn the field off
        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off
 
        // Turn the field off
        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off


@@ -1117,125 +1462,126 @@ void T55xxResetRead(void) {
 }
 
 // Write one card block in page 0, no lock
 }
 
 // Write one card block in page 0, no lock

-void T55xxWriteBlockExt(uint32_t Data, uint32_t Block, uint32_t Pwd, uint8_t arg) {
-       LED_A_ON();
-       bool PwdMode = arg & 0x1;
-       uint8_t Page = (arg & 0x2)>>1;
-       uint32_t i = 0;
-
-       // Set up FPGA, 125kHz
-       LFSetupFPGAForADC(95, true);
-
-       // Trigger T55x7 in mode.
-       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-       SpinDelayUs(START_GAP);
-
-       // Opcode 10
-       T55xxWriteBit(1);
-       T55xxWriteBit(Page); //Page 0
-       if (PwdMode){
-               // Send Pwd
-               for (i = 0x80000000; i != 0; i >>= 1)
-                       T55xxWriteBit(Pwd & i);
-       }
-       // Send Lock bit
-       T55xxWriteBit(0);
-
-       // Send Data
-       for (i = 0x80000000; i != 0; i >>= 1)
-               T55xxWriteBit(Data & i);
-
-       // Send Block number
-       for (i = 0x04; i != 0; i >>= 1)
-               T55xxWriteBit(Block & i);
+void T55xxWriteBlock(uint32_t Data, uint32_t Block, uint32_t Pwd, uint8_t arg) {
+       /*
+               arg bits
+               xxxxxxx1 0x01 PwdMode
+               xxxxxx1x 0x02 Page
+               xxxxx1xx 0x04 testMode
+               xxx11xxx 0x18 downlink mode
+               xx1xxxxx 0x20 !reg_readmode
+               x1xxxxxx 0x40 called for a read, so no data packet
+               1xxxxxxx 0x80 reset
+       */
+       
+       bool    testMode                = ((arg & 0x04) == 0x04);
+       arg &= (0xff ^ 0x40); // Called for a write, so ensure it is clear/0
+       
+       LED_A_ON ();
+       T55xx_SendCMD (Data, Block, Pwd, arg) ;//, false); 

 
        // Perform write (nominal is 5.6 ms for T55x7 and 18ms for E5550,
        // so wait a little more)
 
        // Perform write (nominal is 5.6 ms for T55x7 and 18ms for E5550,
        // so wait a little more)

-       TurnReadLFOn(20 * 1000);
+
+       // "there is a clock delay before programming" 
+       //  - programming takes ~5.6ms for t5577 ~18ms for E5550 or t5567
+       //  so we should wait 1 clock + 5.6ms then read response? 
+       //  but we need to know we are dealing with t5577 vs t5567 vs e5550 (or q5) marshmellow...
+       if (testMode) {
+               //TESTMODE TIMING TESTS: 
+               // <566us does nothing 
+               // 566-568 switches between wiping to 0s and doing nothing
+               // 5184 wipes and allows 1 block to be programmed.
+               // indefinite power on wipes and then programs all blocks with bitshifted data sent.
+               TurnReadLFOn(5184); 
+
+       } else {
+               TurnReadLFOn(20 * 1000);

                //could attempt to do a read to confirm write took
                // as the tag should repeat back the new block 
                // until it is reset, but to confirm it we would 
                //could attempt to do a read to confirm write took
                // as the tag should repeat back the new block 
                // until it is reset, but to confirm it we would 

-               // need to know the current block 0 config mode
+               // need to know the current block 0 config mode for
+               // modulation clock an other details to demod the response...
+               // response should be (for t55x7) a 0 bit then (ST if on) 
+               // block data written in on repeat until reset. 

 
 

+               //DoPartialAcquisition(20, true, 12000);
+       }

        // turn field off
        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
        // turn field off
        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

-       LED_A_OFF();
-}
-
-// Write one card block in page 0, no lock
-void T55xxWriteBlock(uint32_t Data, uint32_t Block, uint32_t Pwd, uint8_t arg) {
-       T55xxWriteBlockExt(Data, Block, Pwd, arg);
+               

        cmd_send(CMD_ACK,0,0,0,0,0);
        cmd_send(CMD_ACK,0,0,0,0,0);

+
+       LED_A_OFF ();

 }
 
 // Read one card block in page [page]
 }
 
 // Read one card block in page [page]

-void T55xxReadBlock(uint16_t arg0, uint8_t Block, uint32_t Pwd) {
+void T55xxReadBlock (uint16_t arg0, uint8_t Block, uint32_t Pwd) {//, struct T55xx_Timing *Timing) {
+       

        LED_A_ON();
        LED_A_ON();

-       bool PwdMode = arg0 & 0x1;
-       uint8_t Page = (arg0 & 0x2) >> 1;
-       uint32_t i = 0;
-       bool RegReadMode = (Block == 0xFF);

 
 

-       //clear buffer now so it does not interfere with timing later
-       BigBuf_Clear_ext(false);
+       /*
+               arg bits
+               xxxxxxx1 0x01 PwdMode
+               xxxxxx1x 0x02 Page
+               xxxxx1xx 0x04 testMode
+               xxx11xxx 0x18 downlink mode
+               xx1xxxxx 0x20 !reg_readmode
+               x1xxxxxx 0x40 called for a read, so no data packet
+               1xxxxxxx 0x80 reset
+       */
+       
+       // Set Read Flag to ensure SendCMD does not add "data" to the packet
+       arg0 |= 0x40;

 
 

+       // RegRead Mode true of block 0xff      
+       if (Block == 0xff) arg0 |= 0x20;
+       

        //make sure block is at max 7
        Block &= 0x7;
 
        //make sure block is at max 7
        Block &= 0x7;
 

-       // Set up FPGA, 125kHz to power up the tag
-       LFSetupFPGAForADC(95, true);
-
-       // Trigger T55x7 Direct Access Mode with start gap
-       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-       SpinDelayUs(START_GAP);
-
-       // Opcode 1[page]
-       T55xxWriteBit(1);
-       T55xxWriteBit(Page); //Page 0
-
-       if (PwdMode){
-               // Send Pwd
-               for (i = 0x80000000; i != 0; i >>= 1)
-                       T55xxWriteBit(Pwd & i);
-       }
-       // Send a zero bit separation
-       T55xxWriteBit(0);
-
-       // Send Block number (if direct access mode)
-       if (!RegReadMode)
-               for (i = 0x04; i != 0; i >>= 1)
-                       T55xxWriteBit(Block & i);               
+       //clear buffer now so it does not interfere with timing later
+       BigBuf_Clear_ext(false);
+       
+       T55xx_SendCMD (0, Block, Pwd, arg0); //, true);

 
        // Turn field on to read the response
 
        // Turn field on to read the response

-       TurnReadLFOn(READ_GAP);
+       // 137*8 seems to get to the start of data pretty well... 
+       //  but we want to go past the start and let the repeating data settle in...
+       TurnReadLFOn(210*8); 

 
        // Acquisition
 
        // Acquisition

-       doT55x7Acquisition(12000);
+       // Now do the acquisition
+       DoPartialAcquisition(0, true, 12000, 0);

 
        // Turn the field off
        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off
        cmd_send(CMD_ACK,0,0,0,0,0);    
 
        // Turn the field off
        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off
        cmd_send(CMD_ACK,0,0,0,0,0);    

+

        LED_A_OFF();
 }
 
 void T55xxWakeUp(uint32_t Pwd){
        LED_B_ON();
        LED_A_OFF();
 }
 
 void T55xxWakeUp(uint32_t Pwd){
        LED_B_ON();

-       uint32_t i = 0;
-       
-       // Set up FPGA, 125kHz
-       LFSetupFPGAForADC(95, true);
-       
-       // Trigger T55x7 Direct Access Mode
-       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-       SpinDelayUs(START_GAP);
+       /*
+               arg bits
+               xxxxxxx1 0x01 PwdMode
+               xxxxxx1x 0x02 Page
+               xxxxx1xx 0x04 testMode
+               xxx11xxx 0x18 downlink mode
+               xx1xxxxx 0x20 !reg_readmode 
+               x1xxxxxx 0x40 called for a read, so no data packet
+               1xxxxxxx 0x80 reset
+       */

        
        

-       // Opcode 10
-       T55xxWriteBit(1);
-       T55xxWriteBit(0); //Page 0
+    // r* 10 (00) <pwd>   r* for llr , L0 and 1/4 - (00) for L0 and 1/4 - All handled in SendCMD
+    // So, default Opcode 10 and pwd.
+    uint8_t arg = 0x01 | 0x40 | 0x20; //Password Read Call no data | reg_read no block
+    
+    // Add in downlink_mode when ready
+    //    arg |= 0x00;  // dlmode << 3  (00 default - 08 leading 0 - 10 Fixed - 18 1 of 4 )

 
 

-       // Send Pwd
-       for (i = 0x80000000; i != 0; i >>= 1)
-               T55xxWriteBit(Pwd & i);
+       T55xx_SendCMD (0, 0, Pwd, arg); //, true);

 
        // Turn and leave field on to let the begin repeating transmission
        TurnReadLFOn(20*1000);
 
        // Turn and leave field on to let the begin repeating transmission
        TurnReadLFOn(20*1000);


@@ -1246,12 +1592,13 @@ void T55xxWakeUp(uint32_t Pwd){
 void WriteT55xx(uint32_t *blockdata, uint8_t startblock, uint8_t numblocks) {
        // write last block first and config block last (if included)
        for (uint8_t i = numblocks+startblock; i > startblock; i--) {
 void WriteT55xx(uint32_t *blockdata, uint8_t startblock, uint8_t numblocks) {
        // write last block first and config block last (if included)
        for (uint8_t i = numblocks+startblock; i > startblock; i--) {

-               T55xxWriteBlockExt(blockdata[i-1],i-1,0,0);
+                T55xxWriteBlock(blockdata[i-1],i-1,0,0);//,false); //,&T55xx_Timing_FixedBit);
+       //      T55xx_SendCMD (blockdata[i-1],i-1,0,0);//,false); //,&T55xx_Timing_FixedBit);

        }
 }
 
        }
 }
 

-// Copy HID id to card and setup block 0 config
-void CopyHIDtoT55x7(uint32_t hi2, uint32_t hi, uint32_t lo, uint8_t longFMT) {
+// Copy a HID-like card (e.g. HID Proximity, Paradox) to a T55x7 compatible card
+void CopyHIDtoT55x7(uint32_t hi2, uint32_t hi, uint32_t lo, uint8_t longFMT, uint8_t preamble) {

        uint32_t data[] = {0,0,0,0,0,0,0};
        uint8_t last_block = 0;
 
        uint32_t data[] = {0,0,0,0,0,0,0};
        uint8_t last_block = 0;
 


@@ -1263,15 +1610,15 @@ void CopyHIDtoT55x7(uint32_t hi2, uint32_t hi, uint32_t lo, uint8_t longFMT) {
                }
                // Build the 6 data blocks for supplied 84bit ID
                last_block = 6;
                }
                // Build the 6 data blocks for supplied 84bit ID
                last_block = 6;

-               // load preamble (1D) & long format identifier (9E manchester encoded)
-               data[1] = 0x1D96A900 | (manchesterEncode2Bytes((hi2 >> 16) & 0xF) & 0xFF);
+               // load preamble & long format identifier (9E manchester encoded)
+               data[1] = (preamble << 24) | 0x96A900 | (manchesterEncode2Bytes((hi2 >> 16) & 0xF) & 0xFF);

                // load raw id from hi2, hi, lo to data blocks (manchester encoded)
                data[2] = manchesterEncode2Bytes(hi2 & 0xFFFF);
                data[3] = manchesterEncode2Bytes(hi >> 16);
                data[4] = manchesterEncode2Bytes(hi & 0xFFFF);
                data[5] = manchesterEncode2Bytes(lo >> 16);
                data[6] = manchesterEncode2Bytes(lo & 0xFFFF);
                // load raw id from hi2, hi, lo to data blocks (manchester encoded)
                data[2] = manchesterEncode2Bytes(hi2 & 0xFFFF);
                data[3] = manchesterEncode2Bytes(hi >> 16);
                data[4] = manchesterEncode2Bytes(hi & 0xFFFF);
                data[5] = manchesterEncode2Bytes(lo >> 16);
                data[6] = manchesterEncode2Bytes(lo & 0xFFFF);

-       }       else {
+       } else {

                // Ensure no more than 44 bits supplied
                if (hi>0xFFF) {
                        DbpString("Tags can only have 44 bits.");
                // Ensure no more than 44 bits supplied
                if (hi>0xFFF) {
                        DbpString("Tags can only have 44 bits.");


@@ -1280,7 +1627,7 @@ void CopyHIDtoT55x7(uint32_t hi2, uint32_t hi, uint32_t lo, uint8_t longFMT) {
                // Build the 3 data blocks for supplied 44bit ID
                last_block = 3;
                // load preamble
                // Build the 3 data blocks for supplied 44bit ID
                last_block = 3;
                // load preamble

-               data[1] = 0x1D000000 | (manchesterEncode2Bytes(hi) & 0xFFFFFF);
+               data[1] = (preamble << 24) | (manchesterEncode2Bytes(hi) & 0xFFFFFF);

                data[2] = manchesterEncode2Bytes(lo >> 16);
                data[3] = manchesterEncode2Bytes(lo & 0xFFFF);
        }
                data[2] = manchesterEncode2Bytes(lo >> 16);
                data[3] = manchesterEncode2Bytes(lo & 0xFFFF);
        }


@@ -1333,10 +1680,10 @@ void CopyIndala224toT55x7(uint32_t uid1, uint32_t uid2, uint32_t uid3, uint32_t
        //Program the 7 data blocks for supplied 224bit UID
        uint32_t data[] = {0, uid1, uid2, uid3, uid4, uid5, uid6, uid7};
        // and the block 0 for Indala224 format 
        //Program the 7 data blocks for supplied 224bit UID
        uint32_t data[] = {0, uid1, uid2, uid3, uid4, uid5, uid6, uid7};
        // and the block 0 for Indala224 format 

-       //Config for Indala (RF/32;PSK1 with RF/2;Maxblock=7)
-       data[0] = T55x7_BITRATE_RF_32 | T55x7_MODULATION_PSK1 | (7 << T55x7_MAXBLOCK_SHIFT);
+       //Config for Indala (RF/32;PSK2 with RF/2;Maxblock=7)
+       data[0] = T55x7_BITRATE_RF_32 | T55x7_MODULATION_PSK2 | (7 << T55x7_MAXBLOCK_SHIFT);

        //TODO add selection of chip for Q5 or T55x7
        //TODO add selection of chip for Q5 or T55x7

-       // data[0] = (((32-2)/2)<<T5555_BITRATE_SHIFT) | T5555_MODULATION_PSK1 | 7 << T5555_MAXBLOCK_SHIFT;
+       // data[0] = (((32-2)>>1)<<T5555_BITRATE_SHIFT) | T5555_MODULATION_PSK2 | 7 << T5555_MAXBLOCK_SHIFT;

        WriteT55xx(data, 0, 8);
        //Alternative config for Indala (Extended mode;RF/32;PSK1 with RF/2;Maxblock=7;Inverse data)
        //      T5567WriteBlock(0x603E10E2,0);
        WriteT55xx(data, 0, 8);
        //Alternative config for Indala (Extended mode;RF/32;PSK1 with RF/2;Maxblock=7;Inverse data)
        //      T5567WriteBlock(0x603E10E2,0);


@@ -1345,7 +1692,7 @@ void CopyIndala224toT55x7(uint32_t uid1, uint32_t uid2, uint32_t uid3, uint32_t
 // clone viking tag to T55xx
 void CopyVikingtoT55xx(uint32_t block1, uint32_t block2, uint8_t Q5) {
        uint32_t data[] = {T55x7_BITRATE_RF_32 | T55x7_MODULATION_MANCHESTER | (2 << T55x7_MAXBLOCK_SHIFT), block1, block2};
 // clone viking tag to T55xx
 void CopyVikingtoT55xx(uint32_t block1, uint32_t block2, uint8_t Q5) {
        uint32_t data[] = {T55x7_BITRATE_RF_32 | T55x7_MODULATION_MANCHESTER | (2 << T55x7_MAXBLOCK_SHIFT), block1, block2};

-       if (Q5) data[0] = (32 << T5555_BITRATE_SHIFT) | T5555_MODULATION_MANCHESTER | 2 << T5555_MAXBLOCK_SHIFT;
+       if (Q5) data[0] = T5555_SET_BITRATE(32) | T5555_MODULATION_MANCHESTER | 2 << T5555_MAXBLOCK_SHIFT;

        // Program the data blocks for supplied ID and the block 0 config
        WriteT55xx(data, 0, 3);
        LED_D_OFF();
        // Program the data blocks for supplied ID and the block 0 config
        WriteT55xx(data, 0, 3);
        LED_D_OFF();


@@ -1429,8 +1776,7 @@ void WriteEM410x(uint32_t card, uint32_t id_hi, uint32_t id_lo) {
                }
                data[0] = clock | T55x7_MODULATION_MANCHESTER | (2 << T55x7_MAXBLOCK_SHIFT);
        } else { //t5555 (Q5)
                }
                data[0] = clock | T55x7_MODULATION_MANCHESTER | (2 << T55x7_MAXBLOCK_SHIFT);
        } else { //t5555 (Q5)

-               clock = (clock-2)>>1;  //n = (RF-2)/2
-               data[0] = (clock << T5555_BITRATE_SHIFT) | T5555_MODULATION_MANCHESTER | (2 << T5555_MAXBLOCK_SHIFT);
+               data[0] = T5555_SET_BITRATE(clock) | T5555_MODULATION_MANCHESTER | (2 << T5555_MAXBLOCK_SHIFT);

        }
 
        WriteT55xx(data, 0, 3);
        }
 
        WriteT55xx(data, 0, 3);


@@ -1447,6 +1793,7 @@ void WriteEM410x(uint32_t card, uint32_t id_hi, uint32_t id_lo) {
 #define FWD_CMD_WRITE 0xA
 #define FWD_CMD_READ 0x9
 #define FWD_CMD_DISABLE 0x5
 #define FWD_CMD_WRITE 0xA
 #define FWD_CMD_READ 0x9
 #define FWD_CMD_DISABLE 0x5

+#define FWD_CMD_PROTECT 0x3

 
 uint8_t forwardLink_data[64]; //array of forwarded bits
 uint8_t * forward_ptr; //ptr for forward message preparation
 
 uint8_t forwardLink_data[64]; //array of forwarded bits
 uint8_t * forward_ptr; //ptr for forward message preparation


@@ -1549,29 +1896,27 @@ void SendForward(uint8_t fwd_bit_count) {
        fwd_write_ptr = forwardLink_data;
        fwd_bit_sz = fwd_bit_count;
 
        fwd_write_ptr = forwardLink_data;
        fwd_bit_sz = fwd_bit_count;
 

-       LED_D_ON();
-
-       // Set up FPGA, 125kHz
+       // Set up FPGA, 125kHz or 95 divisor

        LFSetupFPGAForADC(95, true);
 
        // force 1st mod pulse (start gap must be longer for 4305)
        fwd_bit_sz--; //prepare next bit modulation
        fwd_write_ptr++;
        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off
        LFSetupFPGAForADC(95, true);
 
        // force 1st mod pulse (start gap must be longer for 4305)
        fwd_bit_sz--; //prepare next bit modulation
        fwd_write_ptr++;
        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off

-       SpinDelayUs(55*8); //55 cycles off (8us each)for 4305
+       WaitUS(55*8); //55 cycles off (8us each)for 4305  //another reader has 37 here...

        FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);//field on
        FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);//field on

-       SpinDelayUs(16*8); //16 cycles on (8us each)
+       WaitUS(18*8); //18 cycles on (8us each)

 
        // now start writting
        while(fwd_bit_sz-- > 0) { //prepare next bit modulation
                if(((*fwd_write_ptr++) & 1) == 1)
 
        // now start writting
        while(fwd_bit_sz-- > 0) { //prepare next bit modulation
                if(((*fwd_write_ptr++) & 1) == 1)

-                       SpinDelayUs(32*8); //32 cycles at 125Khz (8us each)
+                       WaitUS(32*8); //32 cycles at 125Khz (8us each)

                else {
                        //These timings work for 4469/4269/4305 (with the 55*8 above)
                        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off
                else {
                        //These timings work for 4469/4269/4305 (with the 55*8 above)
                        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off

-                       SpinDelayUs(23*8); //16-4 cycles off (8us each)
+                       WaitUS(23*8); //23 cycles off (8us each)

                        FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);//field on
                        FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);//field on

-                       SpinDelayUs(9*8); //16 cycles on (8us each)
+                       WaitUS(18*8); //18 cycles on (8us each)

                }
        }
 }
                }
        }
 }


@@ -1593,13 +1938,12 @@ void EM4xLogin(uint32_t Password) {
 void EM4xReadWord(uint8_t Address, uint32_t Pwd, uint8_t PwdMode) {
 
        uint8_t fwd_bit_count;
 void EM4xReadWord(uint8_t Address, uint32_t Pwd, uint8_t PwdMode) {
 
        uint8_t fwd_bit_count;

-       uint8_t *dest = BigBuf_get_addr();
-       uint16_t bufferlength = BigBuf_max_traceLen();
-       uint32_t i = 0;

 
        // Clear destination buffer before sending the command
        BigBuf_Clear_ext(false);
 
 
        // Clear destination buffer before sending the command
        BigBuf_Clear_ext(false);
 

+       LED_A_ON();
+       StartTicks();

        //If password mode do login
        if (PwdMode == 1) EM4xLogin(Pwd);
 
        //If password mode do login
        if (PwdMode == 1) EM4xLogin(Pwd);
 


@@ -1607,36 +1951,29 @@ void EM4xReadWord(uint8_t Address, uint32_t Pwd, uint8_t PwdMode) {
        fwd_bit_count = Prepare_Cmd( FWD_CMD_READ );
        fwd_bit_count += Prepare_Addr( Address );
 
        fwd_bit_count = Prepare_Cmd( FWD_CMD_READ );
        fwd_bit_count += Prepare_Addr( Address );
 

-       // Connect the A/D to the peak-detected low-frequency path.
-       SetAdcMuxFor(GPIO_MUXSEL_LOPKD);
-       // Now set up the SSC to get the ADC samples that are now streaming at us.
-       FpgaSetupSsc();
-

        SendForward(fwd_bit_count);
        SendForward(fwd_bit_count);

-
+       WaitUS(400);

        // Now do the acquisition
        // Now do the acquisition

-       i = 0;
-       for(;;) {
-               if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
-                       AT91C_BASE_SSC->SSC_THR = 0x43;
-               }
-               if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
-                       dest[i] = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
-                       i++;
-                       if (i >= bufferlength) break;
-               }
-       }
+       DoPartialAcquisition(20, true, 6000, 1000);
+       

        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off
        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off

+       LED_A_OFF();

        cmd_send(CMD_ACK,0,0,0,0,0);
        cmd_send(CMD_ACK,0,0,0,0,0);

-       LED_D_OFF();

 }
 
 }
 

-void EM4xWriteWord(uint32_t Data, uint8_t Address, uint32_t Pwd, uint8_t PwdMode) {
-
+void EM4xWriteWord(uint32_t flag, uint32_t Data, uint32_t Pwd) {
+       
+       bool PwdMode = (flag & 0x1);
+       uint8_t Address = (flag >> 8) & 0xFF;

        uint8_t fwd_bit_count;
 
        uint8_t fwd_bit_count;
 

+       //clear buffer now so it does not interfere with timing later
+       BigBuf_Clear_ext(false);
+
+       LED_A_ON();
+       StartTicks();

        //If password mode do login
        //If password mode do login

-       if (PwdMode == 1) EM4xLogin(Pwd);
+       if (PwdMode) EM4xLogin(Pwd);

 
        forward_ptr = forwardLink_data;
        fwd_bit_count = Prepare_Cmd( FWD_CMD_WRITE );
 
        forward_ptr = forwardLink_data;
        fwd_bit_count = Prepare_Cmd( FWD_CMD_WRITE );


@@ -1646,7 +1983,105 @@ void EM4xWriteWord(uint32_t Data, uint8_t Address, uint32_t Pwd, uint8_t PwdMode
        SendForward(fwd_bit_count);
 
        //Wait for write to complete
        SendForward(fwd_bit_count);
 
        //Wait for write to complete

-       SpinDelay(20);
+       //SpinDelay(10);
+
+       WaitUS(6500);
+       //Capture response if one exists
+       DoPartialAcquisition(20, true, 6000, 1000);
+

        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off
        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off

-       LED_D_OFF();
+       LED_A_OFF();
+       cmd_send(CMD_ACK,0,0,0,0,0);
+}
+
+void EM4xProtect(uint32_t flag, uint32_t Data, uint32_t Pwd) {
+       
+       bool PwdMode = (flag & 0x1);
+       uint8_t fwd_bit_count;
+
+       //clear buffer now so it does not interfere with timing later
+       BigBuf_Clear_ext(false);
+
+       LED_A_ON();
+       StartTicks();
+       //If password mode do login
+       if (PwdMode) EM4xLogin(Pwd);
+
+       forward_ptr = forwardLink_data;
+       fwd_bit_count = Prepare_Cmd( FWD_CMD_PROTECT );
+
+       //unsure if this needs the full packet config...
+       fwd_bit_count += Prepare_Data( Data&0xFFFF, Data>>16 );
+
+       SendForward(fwd_bit_count);
+
+       //Wait for write to complete
+       //SpinDelay(10);
+
+       WaitUS(6500);
+       //Capture response if one exists
+       DoPartialAcquisition(20, true, 6000, 1000);
+
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off
+       LED_A_OFF();
+       cmd_send(CMD_ACK,0,0,0,0,0);
+}
+/*
+Reading a COTAG.
+
+COTAG needs the reader to send a startsequence and the card has an extreme slow datarate.
+because of this, we can "sample" the data signal but we interpreate it to Manchester direct.
+
+READER START SEQUENCE:
+burst 800 us,    gap   2.2 msecs
+burst 3.6 msecs  gap   2.2 msecs
+burst 800 us     gap   2.2 msecs
+pulse 3.6 msecs
+
+This triggers a COTAG tag to response
+*/
+void Cotag(uint32_t arg0) {
+
+#define OFF     { FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); WaitUS(2035); }
+#define ON(x)   { FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD); WaitUS((x)); }
+
+       uint8_t rawsignal = arg0 & 0xF;
+
+       LED_A_ON();
+
+       // Switching to LF image on FPGA. This might empty BigBuff
+       FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
+
+       //clear buffer now so it does not interfere with timing later
+       BigBuf_Clear_ext(false);
+
+       // Set up FPGA, 132kHz to power up the tag
+       FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 89);
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
+
+       // Connect the A/D to the peak-detected low-frequency path.
+       SetAdcMuxFor(GPIO_MUXSEL_LOPKD);
+
+       // Now set up the SSC to get the ADC samples that are now streaming at us.
+       FpgaSetupSsc(FPGA_MAJOR_MODE_LF_ADC);
+
+       // start clock - 1.5ticks is 1us
+       StartTicks();
+
+       //send COTAG start pulse
+       ON(740)  OFF
+       ON(3330) OFF
+       ON(740)  OFF
+       ON(1000)
+
+       switch(rawsignal) {
+               case 0: doCotagAcquisition(50000); break;
+               case 1: doCotagAcquisitionManchester(); break;
+               case 2: DoAcquisition_config(true, 0); break;
+       }
+
+       // Turn the field off
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off
+       cmd_send(CMD_ACK,0,0,0,0,0);
+       LED_A_OFF();

 }
 }