lf cmdread: add -k to keep field on

CHANGELOG.md

@@ -3,6 +3,7 @@ All notable changes to this project will be documented in this file.
 This project uses the changelog in accordance with [keepchangelog](http://keepachangelog.com/). Please use this to write notable changes, which is not the same as git commit log...
 
 ## [unreleased][unreleased]
+ - Added option `-k` to `lf cmdread` to keep field on (@doegox)
  - Added `hf mf acl` - decode and print MIFARE access rights (@iceman1001)
  - Added for readline, <tab> autocomplete work inside pm3 client (@iceman1001)
  - Fixed `hf iclass dump` - now uses the right key when suppling credit key (@iceman1001)

armsrc/appmain.c

@@ -823,7 +823,8 @@ static void PacketReceived(PacketCommandNG *packet) {
                 uint16_t period_1;
                 uint8_t  symbol_extra[LF_CMDREAD_MAX_EXTRA_SYMBOLS];
                 uint16_t period_extra[LF_CMDREAD_MAX_EXTRA_SYMBOLS];
-                uint32_t samples : 31;
+                uint32_t samples : 30;
+                bool     keep : 1;
                 bool     verbose : 1;
             } PACKED;
             struct p *payload = (struct p *)packet->data.asBytes;
@@ -831,7 +832,7 @@ static void PacketReceived(PacketCommandNG *packet) {
             uint16_t period_extra[LF_CMDREAD_MAX_EXTRA_SYMBOLS];
             memcpy(symbol_extra, payload->symbol_extra, sizeof(symbol_extra));
             memcpy(period_extra, payload->period_extra, sizeof(period_extra));
-            ModThenAcquireRawAdcSamples125k(payload->delay, payload->period_0, payload->period_1, symbol_extra, period_extra, packet->data.asBytes + sizeof(struct p), payload->verbose, payload->samples, true);
+            ModThenAcquireRawAdcSamples125k(payload->delay, payload->period_0, payload->period_1, symbol_extra, period_extra, packet->data.asBytes + sizeof(struct p), payload->verbose, payload->keep, payload->samples, true);
             break;
         }
         case CMD_LF_SNIFF_RAW_ADC: {

armsrc/lfops.c

@@ -383,6 +383,8 @@ void loadT55xxConfig(void) {
 #endif
 }
 
+static bool prev_keep = false;
+
 /**
  * Function to do a modulation and then get samples.
  * @param delay_off
@@ -390,24 +392,26 @@ void loadT55xxConfig(void) {
  * @param period_1
  * @param command (in binary char array)
  */
-void ModThenAcquireRawAdcSamples125k(uint32_t delay_off, uint16_t period_0, uint16_t period_1, uint8_t *symbol_extra, uint16_t *period_extra, uint8_t *command, bool verbose, uint32_t samples, bool ledcontrol) {
+void ModThenAcquireRawAdcSamples125k(uint32_t delay_off, uint16_t period_0, uint16_t period_1, uint8_t *symbol_extra, uint16_t *period_extra, uint8_t *command, bool verbose, bool keep_field_on, uint32_t samples, bool ledcontrol) {
 
+    if (!prev_keep){
         FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
-
+    }
     // use lf config settings
     sample_config *sc = getSamplingConfig();
-
     LFSetupFPGAForADC(sc->divisor, true);
     // this causes the field to turn on for uncontrolled amount of time, so we'll turn it off
 
+    if (!prev_keep){
+
         // Make sure the tag is reset
         FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+    }
 
     // start timer
     StartTicks();
 
     WaitMS(100);
-
     // clear read buffer
     BigBuf_Clear_keep_EM();
 
@@ -494,8 +498,10 @@ void ModThenAcquireRawAdcSamples125k(uint32_t delay_off, uint16_t period_0, uint
     DoAcquisition_config(verbose, samples, ledcontrol);
 
     // Turn off antenna
+    if (!keep_field_on) {
         FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-
+    }
+    prev_keep = keep_field_on;
     // tell client we are done
     reply_ng(CMD_LF_MOD_THEN_ACQ_RAW_ADC, PM3_SUCCESS, NULL, 0);
 }

armsrc/lfops.h

@@ -15,7 +15,7 @@
 
 #include "pm3_cmd.h" // struct
 
-void ModThenAcquireRawAdcSamples125k(uint32_t delay_off, uint16_t period_0, uint16_t period_1, uint8_t *symbol_extra, uint16_t *period_extra, uint8_t *command, bool verbose, uint32_t samples, bool ledcontrol);
+void ModThenAcquireRawAdcSamples125k(uint32_t delay_off, uint16_t period_0, uint16_t period_1, uint8_t *symbol_extra, uint16_t *period_extra, uint8_t *command, bool verbose, bool keep_field_on, uint32_t samples, bool ledcontrol);
 void ReadTItag(bool ledcontrol);
 void WriteTItag(uint32_t idhi, uint32_t idlo, uint16_t crc, bool ledcontrol);
 

client/src/cmdlf.c

@@ -231,6 +231,7 @@ int CmdLFCommandRead(const char *Cmd) {
         arg_u64_0("z", "zero", "<us>", "ZERO time period"),
         arg_u64_0("s", "samples", "<dec>", "number of samples to collect"),
         arg_lit0("v", "verbose", "verbose output"),
+        arg_lit0("k", "keep", "keep signal field ON after receive"),
         arg_lit0("@", NULL, "continuous mode"),
         arg_param_end
     };
@@ -249,7 +250,8 @@ int CmdLFCommandRead(const char *Cmd) {
     uint16_t period_0 = arg_get_u32_def(ctx, 5, 0);
     uint32_t samples = arg_get_u32_def(ctx, 6, 0);
     bool verbose = arg_get_lit(ctx, 7);
-    bool cm = arg_get_lit(ctx, 8);
+    bool keep_field_on = arg_get_lit(ctx, 8);
+    bool cm = arg_get_lit(ctx, 9);
     CLIParserFree(ctx);
 
     if (g_session.pm3_present == false)
@@ -262,7 +264,8 @@ int CmdLFCommandRead(const char *Cmd) {
         uint16_t period_1;
         uint8_t  symbol_extra[LF_CMDREAD_MAX_EXTRA_SYMBOLS];
         uint16_t period_extra[LF_CMDREAD_MAX_EXTRA_SYMBOLS];
-        uint32_t samples : 31;
+        uint32_t samples : 30;
+        bool     keep_field_on : 1;
         bool     verbose : 1;
         uint8_t data[PM3_CMD_DATA_SIZE - PAYLOAD_HEADER_SIZE];
     } PACKED payload;
@@ -270,6 +273,7 @@ int CmdLFCommandRead(const char *Cmd) {
     payload.period_1 = period_1;
     payload.period_0 = period_0;
     payload.samples = samples;
+    payload.keep_field_on = keep_field_on;
     payload.verbose = verbose;
     memcpy(payload.data, cmd, cmd_len);