// 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
//-----------------------------------------------------------------------------
*/
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
-
- 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();
+ // use lf config settings
+ sample_config *sc = getSamplingConfig();
- /* Make sure the tag is reset */
+ // Make sure the tag is reset
FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
- SpinDelay(2500);
+ WaitMS(2500);
+
+ // clear read buffer (after fpga bitstream loaded...)
+ BigBuf_Clear_keep_EM();
- LFSetupFPGAForADC(sc.divisor, 1);
+ // 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 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();
- 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
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
projects / proxmark3-svn / blobdiff