Merge pull request #570 from marshmellow42/master

improve lf cmdread

CHANGELOG.md

@@ -6,6 +6,7 @@ This project uses the changelog in accordance with [keepchangelog](http://keepac
 ## [unreleased][unreleased]
 
 ### Changed
+- Adjusted `lf cmdread` to respond to client when complete and the client will then automatically call `data samples`
 - Improved backdoor detection missbehaving magic s50/1k tag (Fl0-0)
 - Deleted wipe functionality from `hf mf csetuid` (Merlok)
 - Changed `hf mf nested` logic (Merlok)
@@ -21,6 +22,7 @@ This project uses the changelog in accordance with [keepchangelog](http://keepac
 - Changed start sequence in Qt mode (fix: short commands hangs main Qt thread) (Merlok)
 
 ### Added
+- Added a bitbang mode to `lf cmdread` if delay is 0 the cmd bits turn off and on the antenna with 0 and 1 respectively (marshmellow)
 - Added PAC/Stanley detection to lf search (marshmellow)
 - Added lf pac demod and lf pac read - extracts the raw blocks from a PAC/Stanley tag (marshmellow)
 - Added hf mf c* commands compatibity for 4k and gen1b backdoor (Fl0-0)

armsrc/lfops.c

@@ -4,7 +4,7 @@
 // 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
 //-----------------------------------------------------------------------------
 
@@ -28,51 +28,103 @@
  */
 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
+	// use lf config settings
-	// see if 'h' was specified
+	sample_config *sc = getSamplingConfig();
 
-	if (command[strlen((char *) command) - 1] == 'h')
+	// Make sure the tag is reset
-		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 */
 	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();
+
+	// 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);
+		WaitUS(delay_off);
-		FpgaSendCommand(FPGA_CMD_SET_DIVISOR, sc.divisor);
+		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);
+
+	// 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

armsrc/lfsampling.c

@@ -266,7 +266,7 @@ uint32_t SnoopLF()
 }
 
 /**
-* acquisition of Cotag LF signal. Similart to other LF,  since the Cotag has such long datarate RF/384
+* acquisition of Cotag LF signal. Similar to other LF,  since the Cotag has such long datarate RF/384
 * and is Manchester?,  we directly gather the manchester data into bigbuff
 **/
 #define COTAG_T1 384

client/cmdlf.c

@@ -54,26 +54,24 @@ static int CmdHelp(const char *Cmd);
 
 int usage_lf_cmdread(void)
 {
-	PrintAndLog("Usage: lf cmdread d <delay period> z <zero period> o <one period> c <cmdbytes> [H] ");
+	PrintAndLog("Usage: lf cmdread d <delay period> z <zero period> o <one period> c <cmdbytes> ");
 	PrintAndLog("Options:        ");
 	PrintAndLog("       h             This help");
-	PrintAndLog("       L             Low frequency (125 KHz)");
+	PrintAndLog("       d <delay>     delay OFF period between bits (0 for bitbang mode)");
-	PrintAndLog("       H             High frequency (134 KHz)");
+	PrintAndLog("       z <zero>      time period ZERO (antenna off in bitbang mode)");
-	PrintAndLog("       d <delay>     delay OFF period");
+	PrintAndLog("       o <one>       time period ONE (antenna on in bitbang mode)");
-	PrintAndLog("       z <zero>      time period ZERO");
-	PrintAndLog("       o <one>       time period ONE");
 	PrintAndLog("       c <cmd>       Command bytes");
 	PrintAndLog("       ************* All periods in microseconds");
+	PrintAndLog("       ************* Use lf config to configure options.");
 	PrintAndLog("Examples:");
 	PrintAndLog("      lf cmdread d 80 z 100 o 200 c 11000");
-	PrintAndLog("      lf cmdread d 80 z 100 o 100 c 11000 H");
+	PrintAndLog("      lf cmdread d 80 z 100 o 100 c 11000");
 	return 0;
 }
 
 /* send a command before reading */
 int CmdLFCommandRead(const char *Cmd)
 {
-	static char dummy[3] = {0x20,0x00,0x00};
 	UsbCommand c = {CMD_MOD_THEN_ACQUIRE_RAW_ADC_SAMPLES_125K};
 	bool errors = false;
 	//uint8_t divisor = 95; //125khz
@@ -84,14 +82,6 @@ int CmdLFCommandRead(const char *Cmd)
 		{
 		case 'h':
 			return usage_lf_cmdread();
-		case 'H':
-			//divisor = 88;
-			dummy[1]='h';
-			cmdp++;
-			break;
-		case 'L':
-			cmdp++;
-			break;
 		case 'c':
 			param_getstr(Cmd, cmdp+1, (char *)&c.d.asBytes, sizeof(c.d.asBytes));
 			cmdp+=2;
@@ -121,11 +111,13 @@ int CmdLFCommandRead(const char *Cmd)
 	//Validations
 	if(errors) return usage_lf_cmdread();
 	
-	// in case they specified 'H'
-	strcpy((char *)&c.d.asBytes + strlen((char *)c.d.asBytes), dummy);
-
 	clearCommandBuffer();
 	SendCommand(&c);
+
+	WaitForResponse(CMD_ACK,NULL);
+	getSamples(0, true);
+
+
 	return 0;
 }
 

client/cmdmain.c

@@ -162,7 +162,7 @@ bool WaitForResponseTimeoutW(uint32_t cmd, UsbCommand* response, size_t ms_timeo
 		}
 		if (msclock() - start_time > 2000 && show_warning) {
 			PrintAndLog("Waiting for a response from the proxmark...");
-			PrintAndLog("Don't forget to cancel its operation first by pressing on the button");
+			PrintAndLog("You can cancel this operation by pressing the pm3 button");
 			show_warning = false;
 		}
 	}