add bitbang option to lf cmdread

[proxmark3-svn] / armsrc / lfops.c

diff --git a/armsrc/lfops.c b/armsrc/lfops.c
index 4344742b66696cf173490c380401356c4af458db..5e9fb193f239bff1df48898c1daecbc7c26d19b6 100644 (file)
--- a/armsrc/lfops.c
+++ b/armsrc/lfops.c
@@ -29,6 +29,7 @@
 void ModThenAcquireRawAdcSamples125k(uint32_t delay_off, uint32_t period_0, uint32_t period_1, uint8_t *command)
 {
 
+       StartTicks();
        int divisor_used = 95; // 125 KHz
        // see if 'h' was specified
 
@@ -43,36 +44,82 @@ void ModThenAcquireRawAdcSamples125k(uint32_t delay_off, uint32_t period_0, uint
        /* Make sure the tag is reset */
        FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-       SpinDelay(2500);
+       WaitMS(2500);
 
+       //power on
        LFSetupFPGAForADC(sc.divisor, 1);
 
        // And a little more time for the tag to fully power up
-       SpinDelay(2000);
-
+       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
-       while(*command != '\0' && *command != ' ') {
+
+       if (bitbang) {
+               //HACK it appears my loop and if statements take up about 7 us 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 7 in bit bang mode");
+                       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+                       LED_D_OFF();
+                       return;
+               }
+               //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++) {
+               //while(*command != '\0' && *command != ' ') {
+                       // 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 6us 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 6us 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();
-               SpinDelayUs(delay_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')
-                       SpinDelayUs(period_0);
-               else
-                       SpinDelayUs(period_1);
        }
-       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
        DoAcquisition_config(false, 0);
+       // note leaves field on...  (for future commands?)
 }
 
 /* blank r/w tag data stream