From a37228c8c26f32c3462f6b1641e64acddd62e0cc Mon Sep 17 00:00:00 2001
From: marshmellow42 <marshmellowrf@gmail.com>
Date: Mon, 20 Feb 2017 17:39:39 -0500
Subject: [PATCH] shorten em4x05 capture samples

add cap option for 4469
add sample size option for  DoAcquisition so i can limit how many
samples i want to collect.
use with DoPartialAcquisition
---
 armsrc/lfops.c      |  6 +++---
 armsrc/lfsampling.c | 13 +++++++++----
 armsrc/lfsampling.h |  4 +++-
 client/cmdlfem4x.c  |  3 ++-
 4 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/armsrc/lfops.c b/armsrc/lfops.c
index cfe032fc..35f220c0 100644
--- a/armsrc/lfops.c
+++ b/armsrc/lfops.c
@@ -1628,7 +1628,7 @@ void EM4xReadWord(uint8_t Address, uint32_t Pwd, uint8_t PwdMode) {
 	SendForward(fwd_bit_count);
 
 	// Now do the acquisition
-	doT55x7Acquisition(6000);
+	DoPartialAcquisition(20, true, 5500);
 	
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off
 	LED_A_OFF();
@@ -1656,10 +1656,10 @@ void EM4xWriteWord(uint32_t flag, uint32_t Data, uint32_t Pwd) {
 	SendForward(fwd_bit_count);
 
 	//Wait for write to complete
-	SpinDelay(10);
+	//SpinDelay(10);
 
 	//Capture response if one exists
-	DoAcquisition_default(20, TRUE);
+	DoPartialAcquisition(20, true, 5500);
 
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off
 	LED_A_OFF();
diff --git a/armsrc/lfsampling.c b/armsrc/lfsampling.c
index 72aabe00..aff31e9e 100644
--- a/armsrc/lfsampling.c
+++ b/armsrc/lfsampling.c
@@ -119,11 +119,11 @@ void LFSetupFPGAForADC(int divisor, bool lf_field)
  * @param silent - is true, now outputs are made. If false, dbprints the status
  * @return the number of bits occupied by the samples.
  */
-uint32_t DoAcquisition(uint8_t decimation, uint32_t bits_per_sample, bool averaging, int trigger_threshold, bool silent)
+uint32_t DoAcquisition(uint8_t decimation, uint32_t bits_per_sample, bool averaging, int trigger_threshold, bool silent, int bufsize)
 {
 	//.
 	uint8_t *dest = BigBuf_get_addr();
-    int bufsize = BigBuf_max_traceLen();
+	bufsize = (bufsize > 0 && bufsize < BigBuf_max_traceLen()) ? bufsize : BigBuf_max_traceLen();
 
 	//memset(dest, 0, bufsize); //creates issues with cmdread (marshmellow)
 
@@ -213,7 +213,7 @@ uint32_t DoAcquisition(uint8_t decimation, uint32_t bits_per_sample, bool averag
  */
 uint32_t DoAcquisition_default(int trigger_threshold, bool silent)
 {
-	return DoAcquisition(1,8,0,trigger_threshold,silent);
+	return DoAcquisition(1,8,0,trigger_threshold,silent,0);
 }
 uint32_t DoAcquisition_config( bool silent)
 {
@@ -221,7 +221,12 @@ uint32_t DoAcquisition_config( bool silent)
 				  ,config.bits_per_sample
 				  ,config.averaging
 				  ,config.trigger_threshold
-				  ,silent);
+				  ,silent
+				  ,0);
+}
+
+uint32_t DoPartialAcquisition(int trigger_threshold, bool silent, int sample_size) {
+	return DoAcquisition(1,8,0,trigger_threshold,silent,sample_size);
 }
 
 uint32_t ReadLF(bool activeField, bool silent)
diff --git a/armsrc/lfsampling.h b/armsrc/lfsampling.h
index ba4fc3f7..cd774c15 100644
--- a/armsrc/lfsampling.h
+++ b/armsrc/lfsampling.h
@@ -24,9 +24,11 @@ uint32_t SampleLF(bool silent);
 * Initializes the FPGA for snoop-mode (field off), and acquires the samples.
 * @return number of bits sampled
 **/
-
 uint32_t SnoopLF();
 
+// adds sample size to default options
+uint32_t DoPartialAcquisition(int trigger_threshold, bool silent, int sample_size);
+
 /**
  * @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
diff --git a/client/cmdlfem4x.c b/client/cmdlfem4x.c
index e0c415bb..6208e63c 100644
--- a/client/cmdlfem4x.c
+++ b/client/cmdlfem4x.c
@@ -823,8 +823,9 @@ void printEM4x05info(uint8_t chipType, uint8_t cap, uint16_t custCode, uint32_t
 
 	switch (cap) {
 		case 3: PrintAndLog(" Cap Type:   %u | 330pF",cap); break;
-		case 2: PrintAndLog(" Cap Type:   %u | 210pF",cap); break;
+		case 2: PrintAndLog(" Cap Type:   %u | %spF",cap, (chipType==2)? "75":"210"); break;
 		case 1: PrintAndLog(" Cap Type:   %u | 250pF",cap); break;
+		case 0: PrintAndLog(" Cap Type:   %u | no resonant capacitor",cap); break;
 		default: PrintAndLog(" Cap Type:   %u | unknown",cap); break;
 	}
 
-- 
2.39.5