diff --git a/.gitignore b/.gitignore
index fa74326e..4af73fb1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -21,6 +21,7 @@ flasher
 version.c
 lua
 luac
+fpga_compress
 
 fpga/*
 !fpga/tests
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7055d087..57fb549a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -33,6 +33,7 @@ of stream transmissions (marshmellow)
 - Added 'hf snoop'. This command take digitalized signal from FPGA and put in BigBuffer. (pwpiwi + enio)
 - Added Topaz (NFC type 1) protocol support ('hf topaz reader', 'hf list topaz', 'hf 14a raw -T', 'hf topaz snoop'). (piwi)
 - Added option c to 'hf list' (mark CRC bytes) (piwi)
+- Added option `l` or `h` to `hw tune` to save time and unnecessary fpga writes if you are only interested in lf or hf.
 
 ### Changed
 - Added `[l] <length>` option to data printdemodbuffer
diff --git a/armsrc/appmain.c b/armsrc/appmain.c
index 475b1c1b..eded359e 100644
--- a/armsrc/appmain.c
+++ b/armsrc/appmain.c
@@ -182,13 +182,9 @@ int AvgAdc(int ch) // was static - merlok
 	return (a + 15) >> 5;
 }
 
-void MeasureAntennaTuning(void)
+void MeasureAntennaTuningLfOnly(int *vLf125, int *vLf134, int *peakf, int *peakv, uint8_t LF_Results[])
 {
-	uint8_t LF_Results[256];
-	int i, adcval = 0, peak = 0, peakv = 0, peakf = 0; //ptr = 0 
-	int vLf125 = 0, vLf134 = 0, vHf = 0;	// in mV
-
-	LED_B_ON();
+	int i, adcval = 0, peak = 0;
 
 /*
  * Sweeps the useful LF range of the proxmark from
@@ -198,38 +194,67 @@ void MeasureAntennaTuning(void)
  * the resonating frequency of your LF antenna
  * ( hopefully around 95 if it is tuned to 125kHz!)
  */
-  
-  	FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
+
+	FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
 	for (i=255; i>=19; i--) {
-    WDT_HIT();
+		WDT_HIT();
 		FpgaSendCommand(FPGA_CMD_SET_DIVISOR, i);
 		SpinDelay(20);
 		adcval = ((MAX_ADC_LF_VOLTAGE * AvgAdc(ADC_CHAN_LF)) >> 10);
-		if (i==95) 	vLf125 = adcval; // voltage at 125Khz
-		if (i==89) 	vLf134 = adcval; // voltage at 134Khz
+		if (i==95) *vLf125 = adcval; // voltage at 125Khz
+		if (i==89) *vLf134 = adcval; // voltage at 134Khz
 
 		LF_Results[i] = adcval>>8; // scale int to fit in byte for graphing purposes
 		if(LF_Results[i] > peak) {
-			peakv = adcval;
+			*peakv = adcval;
 			peak = LF_Results[i];
-			peakf = i;
+			*peakf = i;
 			//ptr = i;
 		}
 	}
 
 	for (i=18; i >= 0; i--) LF_Results[i] = 0;
-	
-	LED_A_ON();
+
+	return;
+}
+
+void MeasureAntennaTuningHfOnly(int *vHf)
+{
 	// Let the FPGA drive the high-frequency antenna around 13.56 MHz.
-  	FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+	LED_A_ON();
+	FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
 	SpinDelay(20);
-	vHf = (MAX_ADC_HF_VOLTAGE * AvgAdc(ADC_CHAN_HF)) >> 10;
+	*vHf = (MAX_ADC_HF_VOLTAGE * AvgAdc(ADC_CHAN_HF)) >> 10;
+	LED_A_OFF();
+
+	return;
+}
+
+void MeasureAntennaTuning(int mode)
+{
+	uint8_t LF_Results[256] = {0};
+	int peakv = 0, peakf = 0;
+	int vLf125 = 0, vLf134 = 0, vHf = 0; // in mV
+
+	LED_B_ON();
+
+	if (((mode & FLAG_TUNE_ALL) == FLAG_TUNE_ALL) && (FpgaGetCurrent() == FPGA_BITSTREAM_HF)) {
+		// Reverse "standard" order if HF already loaded, to avoid unnecessary swap.
+		MeasureAntennaTuningHfOnly(&vHf);
+		MeasureAntennaTuningLfOnly(&vLf125, &vLf134, &peakf, &peakv, LF_Results);
+	} else {
+		if (mode & FLAG_TUNE_LF) {
+			MeasureAntennaTuningLfOnly(&vLf125, &vLf134, &peakf, &peakv, LF_Results);
+		}
+		if (mode & FLAG_TUNE_HF) {
+			MeasureAntennaTuningHfOnly(&vHf);
+		}
+	}
 
 	cmd_send(CMD_MEASURED_ANTENNA_TUNING, vLf125 | (vLf134<<16), vHf, peakf | (peakv<<16), LF_Results, 256);
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-	LED_A_OFF();
 	LED_B_OFF();
 	return;
 }
@@ -1231,7 +1256,7 @@ void UsbPacketReceived(uint8_t *packet, int len)
 			break;
 
 		case CMD_MEASURE_ANTENNA_TUNING:
-			MeasureAntennaTuning();
+			MeasureAntennaTuning(c->arg[0]);
 			break;
 
 		case CMD_MEASURE_ANTENNA_TUNING_HF:
diff --git a/armsrc/fpgaloader.c b/armsrc/fpgaloader.c
index 308dda8c..e211c12f 100644
--- a/armsrc/fpgaloader.c
+++ b/armsrc/fpgaloader.c
@@ -566,3 +566,7 @@ void Fpga_print_status(void)
 	else if(downloaded_bitstream == FPGA_BITSTREAM_LF) Dbprintf("  mode.............LF");
 	else Dbprintf("  mode.............%d", downloaded_bitstream);
 }
+
+int FpgaGetCurrent() {
+	return downloaded_bitstream;
+}
diff --git a/armsrc/fpgaloader.h b/armsrc/fpgaloader.h
index 38724cdb..7dfc5c12 100644
--- a/armsrc/fpgaloader.h
+++ b/armsrc/fpgaloader.h
@@ -18,6 +18,7 @@ void FpgaSetupSsc(void);
 void SetupSpi(int mode);
 bool FpgaSetupSscDma(uint8_t *buf, int len);
 void Fpga_print_status();
+int FpgaGetCurrent();
 #define FpgaDisableSscDma(void)	AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
 #define FpgaEnableSscDma(void) AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTEN;
 void SetAdcMuxFor(uint32_t whichGpio);
diff --git a/client/cmddata.c b/client/cmddata.c
index c7fdc91e..394dcbc2 100644
--- a/client/cmddata.c
+++ b/client/cmddata.c
@@ -2048,10 +2048,20 @@ int CmdSamples(const char *Cmd)
 
 int CmdTuneSamples(const char *Cmd)
 {
-	int timeout = 0;
+	int timeout = 0, arg = FLAG_TUNE_ALL;
+
+	if(*Cmd == 'l') {
+	  arg = FLAG_TUNE_LF;
+	} else if (*Cmd == 'h') {
+	  arg = FLAG_TUNE_HF;
+	} else if (*Cmd != '\0') {
+	  PrintAndLog("use 'tune' or 'tune l' or 'tune h'");
+	  return 0;
+	}
+
 	printf("\nMeasuring antenna characteristics, please wait...");
 
-	UsbCommand c = {CMD_MEASURE_ANTENNA_TUNING};
+	UsbCommand c = {CMD_MEASURE_ANTENNA_TUNING, {arg, 0, 0}};
 	SendCommand(&c);
 
 	UsbCommand resp;
diff --git a/client/cmdhw.c b/client/cmdhw.c
index 33dc78ae..74e476eb 100644
--- a/client/cmdhw.c
+++ b/client/cmdhw.c
@@ -467,7 +467,7 @@ static command_t CommandTable[] =
 	{"reset",         CmdReset,       0, "Reset the Proxmark3"},
 	{"setlfdivisor",  CmdSetDivisor,  0, "<19 - 255> -- Drive LF antenna at 12Mhz/(divisor+1)"},
 	{"setmux",        CmdSetMux,      0, "<loraw|hiraw|lopkd|hipkd> -- Set the ADC mux to a specific value"},
-	{"tune",          CmdTune,        0, "Measure antenna tuning"},
+	{"tune",          CmdTune,        0, "['l'|'h'] -- Measure antenna tuning (option 'l' or 'h' to limit to LF or HF)"},
 	{"version",       CmdVersion,     0, "Show version information about the connected Proxmark"},
 	{"status",        CmdStatus,      0, "Show runtime status information about the connected Proxmark"},
 	{"ping",          CmdPing,        0, "Test if the pm3 is responsive"},
diff --git a/include/usb_cmd.h b/include/usb_cmd.h
index 8448b06a..6978a3ad 100644
--- a/include/usb_cmd.h
+++ b/include/usb_cmd.h
@@ -228,6 +228,11 @@ typedef struct{
 #define FLAG_ICLASS_READER_CEDITKEY     0x40
 
 
+//hw tune args
+#define FLAG_TUNE_LF   1
+#define FLAG_TUNE_HF   2
+#define FLAG_TUNE_ALL  3
+
 
 // CMD_DEVICE_INFO response packet has flags in arg[0], flag definitions:
 /* Whether a bootloader that understands the common_area is present */