Some minor fixes

Use longer timeout in WaitForRawDataTimeout() to handle CMD_WTX
Fix a wrong type
Apply changes to other similar part
Remove unused instructions

armsrc/fpgaloader.c

@@ -493,7 +493,7 @@ void FpgaDownloadAndGo(int bitstream_version) {
 #endif
 
     // Send waiting time extension request as this will take a while
-    send_wtx(1500);
+    send_wtx(FPGA_LOAD_WAIT_TIME);
 
     bool verbose = (g_dbglevel > 3);
 

armsrc/lfsampling.c

@@ -229,7 +229,7 @@ void logSample(uint8_t sample, uint8_t decimation, uint8_t bits_per_sample, bool
 
         // write the current byte
         data.buffer[data.numbits >> 3] |= sample >> bits_offset;
-        int numbits = data.numbits + bits_cap;
+        uint32_t numbits = data.numbits + bits_cap;
 
         // write the remaining bits to the next byte
         data.buffer[numbits >> 3] |= sample << (bits_cap);
@@ -306,7 +306,7 @@ uint32_t DoAcquisition(uint8_t decimation, uint8_t bits_per_sample, bool avg, in
 
         // only every 4000th times, in order to save time when collecting samples.
         // interruptible only when logging not yet triggered
-        if ((checked >= 4000) && trigger_hit == false) {
+        if (unlikely(trigger_hit == false && (checked >= 4000))) {
             if (data_available()) {
                 checked = -1;
                 break;
@@ -325,11 +325,11 @@ uint32_t DoAcquisition(uint8_t decimation, uint8_t bits_per_sample, bool avg, in
         if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
             volatile uint8_t sample = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
 
-            // Test point 8 (TP8) can be used to trigger oscilloscope
+            // (RDV4) Test point 8 (TP8) can be used to trigger oscilloscope
             if (ledcontrol) LED_D_OFF();
 
             // threshold either high or low values 128 = center 0.  if trigger = 178
-            if (trigger_hit == false) {
+            if (unlikely(trigger_hit == false)) {
                 if ((trigger_threshold > 0) && (sample < (trigger_threshold + 128)) && (sample > (128 - trigger_threshold))) {
                     if (cancel_after > 0) {
                         cancel_counter++;
@@ -338,11 +338,10 @@ uint32_t DoAcquisition(uint8_t decimation, uint8_t bits_per_sample, bool avg, in
                     }
                     continue;
                 }
+                trigger_hit = true;
             }
 
-            trigger_hit = true;
+            if (unlikely(samples_to_skip > 0)) {
-
-            if (samples_to_skip > 0) {
                 samples_to_skip--;
                 continue;
             }
@@ -371,6 +370,7 @@ uint32_t DoAcquisition(uint8_t decimation, uint8_t bits_per_sample, bool avg, in
     }
     return data.numbits;
 }
+
 /**
  * @brief Does sample acquisition, ignoring the config values set in the sample_config.
  * This method is typically used by tag-specific readers who just wants to read the samples
@@ -441,7 +441,7 @@ int ReadLF_realtime(bool reader_field) {
     int32_t samples_to_skip = config.samples_to_skip;
     const uint8_t decimation = config.decimation;
 
-    uint32_t sample_size = 64;
+    uint32_t sample_buffer_len = 64;
     const int8_t size_threshold_table[9] = {0, 64, 64, 60, 64, 60, 60, 56, 64};
     const int8_t size_threshold = size_threshold_table[bits_per_sample];
 
@@ -450,14 +450,11 @@ int ReadLF_realtime(bool reader_field) {
     uint8_t curr_byte = 0;
     int return_value = PM3_SUCCESS;
 
-    initSampleBuffer(&sample_size); // sample size in bytes
+    initSampleBuffer(&sample_buffer_len);
-    if (sample_size != 64) {
+    if (sample_buffer_len != 64) {
         return PM3_EFAILED;
     }
 
-    sample_size <<= 3; // sample size in bits
-    sample_size /= bits_per_sample; // sample count
-
     bool trigger_hit = false;
     int16_t checked = 0;
 

armsrc/lfzx.c

@@ -153,7 +153,7 @@ static void zx_get(bool ledcontrol) {
             volatile uint8_t sample = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
             (void)sample;
 
-            // Test point 8 (TP8) can be used to trigger oscilloscope
+            // (RDV4) Test point 8 (TP8) can be used to trigger oscilloscope
             if (ledcontrol) LED_D_OFF();
 
         }

client/src/cmdlf.c

@@ -721,7 +721,7 @@ static int lf_read_internal(bool realtime, bool verbose, uint64_t samples) {
         sample_bytes = (sample_bytes / 8) + (sample_bytes % 8 != 0);
 
         SendCommandNG(CMD_LF_ACQ_RAW_ADC, (uint8_t *)&payload, sizeof(payload));
-        sample_bytes = WaitForRawDataTimeout(realtimeBuf, sample_bytes, 1000, true);
+        sample_bytes = WaitForRawDataTimeout(realtimeBuf, sample_bytes, 1000 + FPGA_LOAD_WAIT_TIME, true);
         samples = sample_bytes * 8 / bits_per_sample;
         getSamplesFromBufEx(realtimeBuf, samples, bits_per_sample, verbose);
 
@@ -751,6 +751,7 @@ int lf_read(bool verbose, uint64_t samples) {
 }
 
 int CmdLFRead(const char *Cmd) {
+    // In real-time mode, the first few bytes might be the response of CMD_WTX rather than the real samples
     CLIParserContext *ctx;
     CLIParserInit(&ctx, "lf read",
                   "Sniff low frequency signal.\n"
@@ -816,7 +817,7 @@ int lf_sniff(bool realtime, bool verbose, uint64_t samples) {
         sample_bytes = (sample_bytes / 8) + (sample_bytes % 8 != 0);
 
         SendCommandNG(CMD_LF_SNIFF_RAW_ADC, (uint8_t *)&payload, sizeof(payload));
-        sample_bytes = WaitForRawDataTimeout(realtimeBuf, sample_bytes, 1000, true);
+        sample_bytes = WaitForRawDataTimeout(realtimeBuf, sample_bytes, 1000 + FPGA_LOAD_WAIT_TIME, true);
         samples = sample_bytes * 8 / bits_per_sample;
         getSamplesFromBufEx(realtimeBuf, samples, bits_per_sample, verbose);
 
@@ -842,6 +843,7 @@ int lf_sniff(bool realtime, bool verbose, uint64_t samples) {
 }
 
 int CmdLFSniff(const char *Cmd) {
+    // In real-time mode, the first few bytes might be the response of CMD_WTX rather than the real samples
     CLIParserContext *ctx;
     CLIParserInit(&ctx, "lf sniff",
                   "Sniff low frequency signal. You need to configure the LF part on the Proxmark3 device manually.\n"

include/common.h

@@ -196,6 +196,9 @@ extern bool g_tearoff_enabled;
 #define CLEAR_BIT(data, i) *(data + (i / 8)) &= ~(1 << (7 - (i % 8)))
 #define FLIP_BIT(data, i)  *(data + (i / 8)) ^= (1 << (7 - (i % 8)))
 
+// time for decompressing and loading the image to the FPGA
+#define FPGA_LOAD_WAIT_TIME (1500)
+
 // GCC extension
 // from client/deps/tinycbor/compilersupport_p.h
 #ifdef __GNUC__