diff --git a/CHANGELOG.md b/CHANGELOG.md
index f3e79bfd..044538c4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,8 @@ This project uses the changelog in accordance with [keepchangelog](http://keepac
 - Deleted wipe functionality from `hf mf csetuid` (Merlok)
 - Changed `hf mf nested` logic (Merlok)
 - Added `hf mf nested` mode: autosearch keys for attack (from well known keys) (Merlok)
+- `hf mf nested` Check keys after they have found (Merlok)
+- `hf mf chk` Move main cycle to arm (Merlok)
 - Changed proxmark command line parameter `flush` to `-f` or `-flush` (Merlok)
 
 ### Fixed
@@ -25,6 +27,8 @@ This project uses the changelog in accordance with [keepchangelog](http://keepac
 - Added `hf mf cwipe` command. It wipes "magic Chinese" card. For 1a generation it uses card's "wipe" command. For gen1a and gen1b it uses a write command. (Merlok)
 - Added to `hf mf nested` source key check before attack (Merlok)
 - Added to `hf mf nested` after attack it checks all found keys on non-open sectors (Merlok)
+- `hf mf chk` Added setings to set iso14443a operations timeout. default timeout set to 500us (Merlok)
+- Added to `hf mf nested` parameters `s` and `ss` for checking slow cards (Merlok)
 - Added to proxmark command line parameters `w` - wait 20s for serial port (Merlok)
 - Added to proxmark command line parameters `c` and `l` - execute command and lua script from command line (Merlok)
 - Added to proxmark ability to execute commands from stdin (pipe) (Merlok)
diff --git a/armsrc/apps.h b/armsrc/apps.h
index 1ce3215f..b0070148 100644
--- a/armsrc/apps.h
+++ b/armsrc/apps.h
@@ -127,7 +127,7 @@ void MifareWriteBlock(uint8_t arg0, uint8_t arg1, uint8_t arg2, uint8_t *datain)
 void MifareUWriteBlock(uint8_t arg0, uint8_t arg1, uint8_t *datain);
 void MifareNested(uint32_t arg0, uint32_t arg1, uint32_t arg2, uint8_t *datain);
 void MifareAcquireEncryptedNonces(uint32_t arg0, uint32_t arg1, uint32_t flags, uint8_t *datain);
-void MifareChkKeys(uint16_t arg0, uint8_t arg1, uint8_t arg2, uint8_t *datain);
+void MifareChkKeys(uint16_t arg0, uint16_t arg1, uint8_t arg2, uint8_t *datain);
 void Mifare1ksim(uint8_t arg0, uint8_t arg1, uint8_t arg2, uint8_t *datain);
 void MifareSetDbgLvl(uint32_t arg0, uint32_t arg1, uint32_t arg2, uint8_t *datain);
 void MifareEMemClr(uint32_t arg0, uint32_t arg1, uint32_t arg2, uint8_t *datain);
diff --git a/armsrc/iso14443a.h b/armsrc/iso14443a.h
index 10e50e0f..9977a658 100644
--- a/armsrc/iso14443a.h
+++ b/armsrc/iso14443a.h
@@ -29,4 +29,5 @@ extern void iso14443a_setup(uint8_t fpga_minor_mode);
 extern int iso14_apdu(uint8_t *cmd, uint16_t cmd_len, void *data);
 extern int iso14443a_select_card(uint8_t *uid_ptr, iso14a_card_select_t *resp_data, uint32_t *cuid_ptr, bool anticollision, uint8_t num_cascades, bool no_rats);
 extern void iso14a_set_trigger(bool enable);
+extern void iso14a_set_timeout(uint32_t timeout);
 #endif /* __ISO14443A_H */
diff --git a/armsrc/iso14443b.h b/armsrc/iso14443b.h
index f90c54f3..de6faa92 100644
--- a/armsrc/iso14443b.h
+++ b/armsrc/iso14443b.h
@@ -7,7 +7,7 @@
 // at your option, any later version. See the LICENSE.txt file for the text of
 // the license.
 //-----------------------------------------------------------------------------
-// Routines to support ISO 14443 type A.
+// Routines to support ISO 14443 type B.
 //-----------------------------------------------------------------------------
 
 #ifndef __ISO14443B_H
diff --git a/armsrc/mifarecmd.c b/armsrc/mifarecmd.c
index a3f0d374..edafe0a3 100644
--- a/armsrc/mifarecmd.c
+++ b/armsrc/mifarecmd.c
@@ -20,10 +20,6 @@
 #include "parity.h"
 #include "crc.h"
 
-#define AUTHENTICATION_TIMEOUT 848			// card times out 1ms after wrong authentication (according to NXP documentation)
-#define PRE_AUTHENTICATION_LEADTIME 400		// some (non standard) cards need a pause after select before they are ready for first authentication
-
-
 // the block number for the ISO14443-4 PCB
 static uint8_t pcb_blocknum = 0;
 // Deselect card by sending a s-block. the crc is precalced for speed
@@ -961,24 +957,14 @@ void MifareNested(uint32_t arg0, uint32_t arg1, uint32_t calibrate, uint8_t *dat
 // MIFARE check keys. key count up to 85.
 //
 //-----------------------------------------------------------------------------
-void MifareChkKeys(uint16_t arg0, uint8_t arg1, uint8_t arg2, uint8_t *datain)
+void MifareChkKeys(uint16_t arg0, uint16_t arg1, uint8_t arg2, uint8_t *datain)
 {
 	uint8_t blockNo = arg0 & 0xff;
 	uint8_t keyType = (arg0 >> 8) & 0xff;
-	bool clearTrace = arg1;
+	bool clearTrace = arg1 & 0x01;
+	bool multisectorCheck = arg1 & 0x02;
+	uint8_t set14aTimeout = (arg1 >> 8) & 0xff;
 	uint8_t keyCount = arg2;
-	uint64_t ui64Key = 0;
-
-	bool have_uid = false;
-	uint8_t cascade_levels = 0;
-	uint32_t timeout = 0;
-	int i;
-	byte_t isOK = 0;
-	uint8_t uid[10];
-	uint32_t cuid;
-	struct Crypto1State mpcs = {0, 0};
-	struct Crypto1State *pcs;
-	pcs = &mpcs;
 
 	// clear debug level
 	int OLD_MF_DBGLEVEL = MF_DBGLEVEL;
@@ -992,52 +978,33 @@ void MifareChkKeys(uint16_t arg0, uint8_t arg1, uint8_t arg2, uint8_t *datain)
 	if (clearTrace) clear_trace();
 	set_tracing(true);
 
-	for (i = 0; i < keyCount; i++) {
-//		if(mifare_classic_halt(pcs, cuid)) {
-//			if (MF_DBGLEVEL >= 1)	Dbprintf("ChkKeys: Halt error");
-//		}
-
-		// Iceman: use piwi's faster nonce collecting part in hardnested.
-		if (!have_uid) { // need a full select cycle to get the uid first
-			iso14a_card_select_t card_info;
-			if(!iso14443a_select_card(uid, &card_info, &cuid, true, 0, true)) {
-				if (OLD_MF_DBGLEVEL >= 1) 	Dbprintf("ChkKeys: Can't select card");
-				--i; // try same key once again
-				continue;
-			}
-			switch (card_info.uidlen) {
-				case 4 : cascade_levels = 1; break;
-				case 7 : cascade_levels = 2; break;
-				case 10: cascade_levels = 3; break;
-				default: break;
-			}
-			have_uid = true;
-		} else { // no need for anticollision. We can directly select the card
-			if(!iso14443a_select_card(uid, NULL, NULL, false, cascade_levels, true)) {
-				if (OLD_MF_DBGLEVEL >= 1)	Dbprintf("ChkKeys: Can't select card (UID)");
-				--i; // try same key once again
-				continue;
-			}
-		}
-
-		ui64Key = bytes_to_num(datain + i * 6, 6);
-		if(mifare_classic_auth(pcs, cuid, blockNo, keyType, ui64Key, AUTH_FIRST)) {
-			uint8_t dummy_answer = 0;
-			ReaderTransmit(&dummy_answer, 1, NULL);
-			timeout = GetCountSspClk() + AUTHENTICATION_TIMEOUT;
-
-			// wait for the card to become ready again
-			while(GetCountSspClk() < timeout);
-			continue;
-		}
-
-		isOK = 1;
-		break;
+	if (set14aTimeout){
+		iso14a_set_timeout(set14aTimeout * 10); // timeout: ms = x/106  35-minimum, 50-OK 106-recommended 500-safe
 	}
+	
+	if (multisectorCheck) {
+		TKeyIndex keyIndex = {{0}};
+		uint8_t sectorCnt = blockNo;
+		int res = MifareMultisectorChk(datain, keyCount, sectorCnt, keyType, OLD_MF_DBGLEVEL, &keyIndex);
 
-	LED_B_ON();
-    cmd_send(CMD_ACK,isOK,0,0,datain + i * 6,6);
-	LED_B_OFF();
+		LED_B_ON();
+		if (res >= 0) {
+			cmd_send(CMD_ACK, 1, 0, 0, keyIndex, 80);
+		} else {
+			cmd_send(CMD_ACK, 0, 0, 0, NULL, 0);
+		}
+		LED_B_OFF();
+	} else {	
+		int res = MifareChkBlockKeys(datain, keyCount, blockNo, keyType, OLD_MF_DBGLEVEL);
+		
+		LED_B_ON();
+		if (res > 0) {
+			cmd_send(CMD_ACK, 1, 0, 0, datain + (res - 1) * 6, 6);
+		} else {
+			cmd_send(CMD_ACK, 0, 0, 0, NULL, 0);
+		}
+		LED_B_OFF();
+	}
 
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
 	LEDsoff();
diff --git a/armsrc/mifareutil.c b/armsrc/mifareutil.c
index fdead5ee..97f7b3d1 100644
--- a/armsrc/mifareutil.c
+++ b/armsrc/mifareutil.c
@@ -764,3 +764,125 @@ int mifare_desfire_des_auth2(uint32_t uid, uint8_t *key, uint8_t *blockData){
 	}
 	return 1;
 }
+
+//-----------------------------------------------------------------------------
+// MIFARE check keys
+//
+//-----------------------------------------------------------------------------
+// one key check
+int MifareChkBlockKey(uint8_t *uid, uint32_t *cuid, uint8_t *cascade_levels, uint64_t ui64Key, uint8_t blockNo, uint8_t keyType, uint8_t debugLevel) {
+
+	struct Crypto1State mpcs = {0, 0};
+	struct Crypto1State *pcs;
+	pcs = &mpcs;
+
+	// Iceman: use piwi's faster nonce collecting part in hardnested.
+	if (*cascade_levels == 0) { // need a full select cycle to get the uid first
+		iso14a_card_select_t card_info;
+		if(!iso14443a_select_card(uid, &card_info, cuid, true, 0, true)) {
+			if (debugLevel >= 1) 	Dbprintf("ChkKeys: Can't select card");
+			return  1;
+		}
+		switch (card_info.uidlen) {
+			case 4 : *cascade_levels = 1; break;
+			case 7 : *cascade_levels = 2; break;
+			case 10: *cascade_levels = 3; break;
+			default: break;
+		}
+	} else { // no need for anticollision. We can directly select the card
+		if(!iso14443a_select_card(uid, NULL, NULL, false, *cascade_levels, true)) {
+			if (debugLevel >= 1)	Dbprintf("ChkKeys: Can't select card (UID) lvl=%d", *cascade_levels);
+			return  1;
+		}
+	}
+	
+	if(mifare_classic_auth(pcs, *cuid, blockNo, keyType, ui64Key, AUTH_FIRST)) {
+//		SpinDelayUs(AUTHENTICATION_TIMEOUT); // it not needs because mifare_classic_auth have timeout from iso14a_set_timeout()
+		return 2;
+	} else {
+/*		// let it be here. it like halt command, but maybe it will work in some strange cases
+		uint8_t dummy_answer = 0;
+		ReaderTransmit(&dummy_answer, 1, NULL);
+		int timeout = GetCountSspClk() + AUTHENTICATION_TIMEOUT;			
+		// wait for the card to become ready again
+		while(GetCountSspClk() < timeout) {};
+*/
+		// it needs after success authentication
+		mifare_classic_halt(pcs, *cuid);
+	}
+	
+	return 0;
+}
+
+// multi key check
+int MifareChkBlockKeys(uint8_t *keys, uint8_t keyCount, uint8_t blockNo, uint8_t keyType, uint8_t debugLevel) {
+	uint8_t uid[10];
+	uint32_t cuid = 0;
+	uint8_t cascade_levels = 0;
+	uint64_t ui64Key = 0;
+
+	int retryCount = 0;
+	for (uint8_t i = 0; i < keyCount; i++) {
+
+		// Allow button press / usb cmd to interrupt device
+		if (BUTTON_PRESS() && !usb_poll_validate_length()) { 
+			Dbprintf("ChkKeys: Cancel operation. Exit...");
+			return -2;
+		}
+
+		ui64Key = bytes_to_num(keys + i * 6, 6);
+		int res = MifareChkBlockKey(uid, &cuid, &cascade_levels, ui64Key, blockNo, keyType, debugLevel);
+		
+		// can't select
+		if (res == 1) {
+			retryCount++;
+			if (retryCount >= 5) {
+				Dbprintf("ChkKeys: block=%d key=%d. Can't select. Exit...", blockNo, keyType);
+				return -1;
+			}
+			--i; // try the same key once again
+
+			SpinDelay(20);
+//			Dbprintf("ChkKeys: block=%d key=%d. Try the same key once again...", blockNo, keyType);
+			continue;
+		}
+		
+		// can't authenticate
+		if (res == 2) {
+			retryCount = 0;
+			continue; // can't auth. wrong key.
+		}
+
+		return i + 1;
+	}
+	
+	return 0;
+}
+
+// multisector multikey check
+int MifareMultisectorChk(uint8_t *keys, uint8_t keyCount, uint8_t SectorCount, uint8_t keyType, uint8_t debugLevel, TKeyIndex *keyIndex) {
+	int res = 0;
+	
+//	int clk = GetCountSspClk();
+
+	for(int sc = 0; sc < SectorCount; sc++){
+		WDT_HIT();
+
+		int keyAB = keyType;
+		do {
+			res = MifareChkBlockKeys(keys, keyCount, FirstBlockOfSector(sc), keyAB & 0x01, debugLevel);
+			if (res < 0){
+				return res;
+			}
+			if (res > 0){
+				(*keyIndex)[keyAB & 0x01][sc] = res;
+			}
+		} while(--keyAB > 0);
+	}
+	
+//	Dbprintf("%d %d", GetCountSspClk() - clk, (GetCountSspClk() - clk)/(SectorCount*keyCount*(keyType==2?2:1)));
+	
+	return 0;
+}
+
+
diff --git a/armsrc/mifareutil.h b/armsrc/mifareutil.h
index 468c5cce..8ffd5e89 100644
--- a/armsrc/mifareutil.h
+++ b/armsrc/mifareutil.h
@@ -13,6 +13,7 @@
 #define __MIFAREUTIL_H
 
 #include "crapto1/crapto1.h"
+#include "usb_cdc.h"
 
 // mifare authentication
 #define CRYPT_NONE    0
@@ -20,6 +21,8 @@
 #define CRYPT_REQUEST 2
 #define AUTH_FIRST    0	
 #define AUTH_NESTED   2
+#define AUTHENTICATION_TIMEOUT 848			// card times out 1ms after wrong authentication (according to NXP documentation)
+#define PRE_AUTHENTICATION_LEADTIME 400		// some (non standard) cards need a pause after select before they are ready for first authentication
 
 // mifare 4bit card answers
 #define CARD_ACK      0x0A  // 1010 - ACK
@@ -99,4 +102,10 @@ int emlGetValBl(uint32_t *blReg, uint8_t *blBlock, int blockNum);
 int emlSetValBl(uint32_t blReg, uint8_t blBlock, int blockNum);
 int emlCheckValBl(int blockNum);
 
+// mifare check keys
+typedef uint8_t TKeyIndex[2][40];
+int MifareChkBlockKey(uint8_t *uid, uint32_t *cuid, uint8_t *cascade_levels, uint64_t ui64Key, uint8_t blockNo, uint8_t keyType, uint8_t debugLevel);
+int MifareChkBlockKeys(uint8_t *keys, uint8_t keyCount, uint8_t blockNo, uint8_t keyType, uint8_t debugLevel);
+int MifareMultisectorChk(uint8_t *keys, uint8_t keyCount, uint8_t SectorCount, uint8_t keyType, uint8_t debugLevel, TKeyIndex *keyIndex);
+
 #endif
diff --git a/client/cmdhf.c b/client/cmdhf.c
index eb2ba9b2..6aa5ae4e 100644
--- a/client/cmdhf.c
+++ b/client/cmdhf.c
@@ -546,7 +546,7 @@ uint16_t printTraceLine(uint16_t tracepos, uint16_t traceLen, uint8_t *trace, ui
 	
 	if (showWaitCycles && !isResponse && next_record_is_response(tracepos, trace)) {
 		uint32_t next_timestamp = *((uint32_t *)(trace + tracepos));
-		PrintAndLog(" %9d | %9d | %s | fdt (Frame Delay Time): %d",
+		PrintAndLog(" %10d | %10d | %s | fdt (Frame Delay Time): %d",
 			(EndOfTransmissionTimestamp - first_timestamp),
 			(next_timestamp - first_timestamp),
 			"   ",
diff --git a/client/cmdhfmf.c b/client/cmdhfmf.c
index 295f22b7..553803c1 100644
--- a/client/cmdhfmf.c
+++ b/client/cmdhfmf.c
@@ -524,14 +524,35 @@ int CmdHF14AMfRestore(const char *Cmd)
 	return 0;
 }
 
-
-typedef struct {
-	uint64_t Key[2];
-	int foundKey[2];
-} sector_t;
-
-
+//----------------------------------------------
+//   Nested
+//----------------------------------------------
 # define NESTED_KEY_COUNT 15
+
+static void parseParamTDS(const char *Cmd, const uint8_t indx, bool *paramT, bool *paramD, uint8_t *timeout) {
+	char ctmp3[3] = {0};
+	int len = param_getlength(Cmd, indx);
+	if (len > 0 && len < 4){
+		param_getstr(Cmd, indx, ctmp3);
+		
+		*paramT |= (ctmp3[0] == 't' || ctmp3[0] == 'T');
+		*paramD |= (ctmp3[0] == 'd' || ctmp3[0] == 'D');
+		bool paramS1 = *paramT || *paramD;
+
+		// slow and very slow
+		if (ctmp3[0] == 's' || ctmp3[0] == 'S' || ctmp3[1] == 's' || ctmp3[1] == 'S') {
+			*timeout = 11; // slow
+		
+			if (!paramS1 && (ctmp3[1] == 's' || ctmp3[1] == 'S')) {
+				*timeout = 53; // very slow
+			}
+			if (paramS1 && (ctmp3[2] == 's' || ctmp3[2] == 'S')) {
+				*timeout = 53; // very slow
+			}
+		}
+	}
+}
+
 int CmdHF14AMfNested(const char *Cmd)
 {
 	int i, j, res, iterations;
@@ -544,6 +565,8 @@ int CmdHF14AMfNested(const char *Cmd)
 	uint8_t key[6] = {0, 0, 0, 0, 0, 0};
 	uint8_t keyBlock[NESTED_KEY_COUNT * 6];
 	uint64_t key64 = 0;
+	// timeout in units. (ms * 106)/10 or us*0.0106
+	uint8_t btimeout14a = MF_CHKKEYS_DEFTIMEOUT; // fast by default
 	
 	bool autosearchKey = false;
 
@@ -557,20 +580,23 @@ int CmdHF14AMfNested(const char *Cmd)
 
 	if (strlen(Cmd)<3) {
 		PrintAndLog("Usage:");
-		PrintAndLog(" all sectors:  hf mf nested  <card memory> <block number> <key A/B> <key (12 hex symbols)> [t,d]");
-		PrintAndLog(" all sectors autosearch key:  hf mf nested  <card memory> * [t,d]");
+		PrintAndLog(" all sectors:  hf mf nested  <card memory> <block number> <key A/B> <key (12 hex symbols)> [t|d|s|ss]");
+		PrintAndLog(" all sectors autosearch key:  hf mf nested  <card memory> * [t|d|s|ss]");
 		PrintAndLog(" one sector:   hf mf nested  o <block number> <key A/B> <key (12 hex symbols)>");
 		PrintAndLog("               <target block number> <target key A/B> [t]");
 		PrintAndLog(" ");
 		PrintAndLog("card memory - 0 - MINI(320 bytes), 1 - 1K, 2 - 2K, 4 - 4K, <other> - 1K");
 		PrintAndLog("t - transfer keys to emulator memory");
 		PrintAndLog("d - write keys to binary file dumpkeys.bin");
+		PrintAndLog("s - Slow (1ms) check keys (required by some non standard cards)");
+		PrintAndLog("ss - Very slow (5ms) check keys");
 		PrintAndLog(" ");
 		PrintAndLog("      sample1: hf mf nested 1 0 A FFFFFFFFFFFF ");
 		PrintAndLog("      sample2: hf mf nested 1 0 A FFFFFFFFFFFF t ");
 		PrintAndLog("      sample3: hf mf nested 1 0 A FFFFFFFFFFFF d ");
 		PrintAndLog("      sample4: hf mf nested o 0 A FFFFFFFFFFFF 4 A");
 		PrintAndLog("      sample5: hf mf nested 1 * t");
+		PrintAndLog("      sample6: hf mf nested 1 * ss");
 		return 0;
 	}
 
@@ -587,11 +613,10 @@ int CmdHF14AMfNested(const char *Cmd)
 	if (param_getchar(Cmd, 1) == '*') {
 		autosearchKey = true;
 
-		ctmp = param_getchar(Cmd, 2);
-		transferToEml |= (ctmp == 't' || ctmp == 'T');
-		createDumpFile |= (ctmp == 'd' || ctmp == 'D');
+		parseParamTDS(Cmd, 2, &transferToEml, &createDumpFile, &btimeout14a);
 
-		PrintAndLog("--nested. sectors:%2d, block no:*, eml:%c, dmp=%c ", SectorsCnt, transferToEml?'y':'n', createDumpFile?'y':'n');
+		PrintAndLog("--nested. sectors:%2d, block no:*, eml:%c, dmp=%c checktimeout=%d us", 
+			SectorsCnt, transferToEml?'y':'n', createDumpFile?'y':'n', ((int)btimeout14a * 10000) / 106);
 	} else {
 		blockNo = param_get8(Cmd, 1);
 
@@ -628,16 +653,13 @@ int CmdHF14AMfNested(const char *Cmd)
 			if (ctmp != 'A' && ctmp != 'a')
 				trgKeyType = 1;
 
-			ctmp = param_getchar(Cmd, 6);
-			transferToEml |= (ctmp == 't' || ctmp == 'T');
-			createDumpFile |= (ctmp == 'd' || ctmp == 'D');
+			parseParamTDS(Cmd, 6, &transferToEml, &createDumpFile, &btimeout14a);
 		} else {
-			ctmp = param_getchar(Cmd, 4);
-			transferToEml |= (ctmp == 't' || ctmp == 'T');
-			createDumpFile |= (ctmp == 'd' || ctmp == 'D');
+			parseParamTDS(Cmd, 4, &transferToEml, &createDumpFile, &btimeout14a);
 		}
 
-		PrintAndLog("--nested. sectors:%2d, block no:%3d, key type:%c, eml:%c, dmp=%c ", SectorsCnt, blockNo, keyType?'B':'A', transferToEml?'y':'n', createDumpFile?'y':'n');
+		PrintAndLog("--nested. sectors:%2d, block no:%3d, key type:%c, eml:%c, dmp=%c checktimeout=%d us", 
+			SectorsCnt, blockNo, keyType?'B':'A', transferToEml?'y':'n', createDumpFile?'y':'n', ((int)btimeout14a * 10000) / 106);
 	}
 
 	// one-sector nested
@@ -686,35 +708,12 @@ int CmdHF14AMfNested(const char *Cmd)
 		if (e_sector == NULL) return 1;
 
 		//test current key and additional standard keys first
-		memcpy(keyBlock, key, 6);
-		num_to_bytes(0xffffffffffff, 6, (uint8_t*)(keyBlock + 1 * 6));
-		num_to_bytes(0x000000000000, 6, (uint8_t*)(keyBlock + 2 * 6));
-		num_to_bytes(0xa0a1a2a3a4a5, 6, (uint8_t*)(keyBlock + 3 * 6));
-		num_to_bytes(0xb0b1b2b3b4b5, 6, (uint8_t*)(keyBlock + 4 * 6));
-		num_to_bytes(0xaabbccddeeff, 6, (uint8_t*)(keyBlock + 5 * 6));
-		num_to_bytes(0x4d3a99c351dd, 6, (uint8_t*)(keyBlock + 6 * 6));
-		num_to_bytes(0x1a982c7e459a, 6, (uint8_t*)(keyBlock + 7 * 6));
-		num_to_bytes(0xd3f7d3f7d3f7, 6, (uint8_t*)(keyBlock + 8 * 6));
-		num_to_bytes(0x714c5c886e97, 6, (uint8_t*)(keyBlock + 9 * 6));
-		num_to_bytes(0x587ee5f9350f, 6, (uint8_t*)(keyBlock + 10 * 6));
-		num_to_bytes(0xa0478cc39091, 6, (uint8_t*)(keyBlock + 11 * 6));
-		num_to_bytes(0x533cb6c723f6, 6, (uint8_t*)(keyBlock + 12 * 6));
-		num_to_bytes(0x8fd0a4f256e9, 6, (uint8_t*)(keyBlock + 13 * 6));
-		num_to_bytes(0x1a2b3c4d5e6f, 6, (uint8_t*)(keyBlock + 14 * 6));
+		for (int defaultKeyCounter = 0; defaultKeyCounter < MifareDefaultKeysSize; defaultKeyCounter++){
+			num_to_bytes(MifareDefaultKeys[defaultKeyCounter], 6, (uint8_t*)(keyBlock + defaultKeyCounter * 6));
+		}
 
 		PrintAndLog("Testing known keys. Sector count=%d", SectorsCnt);
-		for (i = 0; i < SectorsCnt; i++) {
-			for (j = 0; j < 2; j++) {
-				if (e_sector[i].foundKey[j]) continue;
-
-				res = mfCheckKeys(FirstBlockOfSector(i), j, true, NESTED_KEY_COUNT, keyBlock, &key64); 
-
-				if (!res) {
-					e_sector[i].Key[j] = key64;
-					e_sector[i].foundKey[j] = 1;
-				}
-			}
-		}
+		mfCheckKeysSec(SectorsCnt, 2, btimeout14a, true, NESTED_KEY_COUNT, keyBlock, e_sector);
 		
 		// get known key from array
 		bool keyFound = false;
@@ -772,6 +771,9 @@ int CmdHF14AMfNested(const char *Cmd)
 						PrintAndLog("Found valid key:%012" PRIx64, key64);
 						e_sector[sectorNo].foundKey[trgKeyType] = 1;
 						e_sector[sectorNo].Key[trgKeyType] = key64;
+						
+						// try to check this key as a key to the other sectors
+						mfCheckKeysSec(SectorsCnt, 2, btimeout14a, true, 1, keyBlock, e_sector);
 					}
 				}
 			}
@@ -781,66 +783,6 @@ int CmdHF14AMfNested(const char *Cmd)
 		PrintAndLog("\n\n-----------------------------------------------\nNested statistic:\nIterations count: %d", iterations);
 		PrintAndLog("Time in nested: %1.3f (%1.3f sec per key)", ((float)(msclock() - msclock1))/1000.0, ((float)(msclock() - msclock1))/iterations/1000.0);
 		
-		// check if we have unrecognized keys
-		bool notFoundKeys = false;
-		for (i = 0; i < SectorsCnt; i++) {
-			for (j = 0; j < 2; j++) {
-				if (!e_sector[i].foundKey[j]) {
-					notFoundKeys = true;
-					break;
-				}
-			}
-			if (notFoundKeys) break;
-		}		
-		
-		if (notFoundKeys) {
-			PrintAndLog("-----------------------------------------------\n");
-			PrintAndLog("We have unrecognized keys. Trying to check if we have this keys on key buffer...");
-
-			// fill keyBlock with known keys
-			int cnt = 0;
-			for (i = 0; i < SectorsCnt; i++) {
-				for (j = 0; j < 2; j++) {
-					if (e_sector[i].foundKey[j]) {
-						// try to insert key to keyBlock						
-						if (cnt < NESTED_KEY_COUNT) {
-
-							// search for dublicates
-							bool dubl = false;
-							for (int v = 0; v < NESTED_KEY_COUNT; v++) {
-								if (e_sector[i].Key[j] == bytes_to_num((uint8_t*)(keyBlock + v * 6), 6)) {
-									dubl = true;
-									break;
-								}
-							}
-							
-							// insert
-							if (!dubl) {
-								num_to_bytes(e_sector[i].Key[j], 6, (uint8_t*)(keyBlock + cnt * 6));
-								cnt++;
-							}
-						}
-					}
-				}
-			}
-
-			// try to auth with known keys to not recognized sectors keys
-			PrintAndLog("Testing keys. Sector count=%d known keys count:%d", SectorsCnt, cnt);
-			for (i = 0; i < SectorsCnt; i++) {
-				for (j = 0; j < 2; j++) {
-					if (e_sector[i].foundKey[j]) continue;
-
-					res = mfCheckKeys(FirstBlockOfSector(i), j, true, cnt, keyBlock, &key64); 
-
-					if (!res) {
-						e_sector[i].Key[j] = key64;
-						e_sector[i].foundKey[j] = 1;
-					}
-				}
-			}			
-			
-		} // if (notFoundKeys)
-		
 		// print result
 		PrintAndLog("|---|----------------|---|----------------|---|");
 		PrintAndLog("|sec|key A           |res|key B           |res|");
@@ -1022,14 +964,18 @@ int CmdHF14AMfNestedHard(const char *Cmd)
 int CmdHF14AMfChk(const char *Cmd)
 {
 	if (strlen(Cmd)<3) {
-		PrintAndLog("Usage:  hf mf chk <block number>|<*card memory> <key type (A/B/?)> [t|d] [<key (12 hex symbols)>] [<dic (*.dic)>]");
+		PrintAndLog("Usage:  hf mf chk <block number>|<*card memory> <key type (A/B/?)> [t|d|s|ss] [<key (12 hex symbols)>] [<dic (*.dic)>]");
 		PrintAndLog("          * - all sectors");
 		PrintAndLog("card memory - 0 - MINI(320 bytes), 1 - 1K, 2 - 2K, 4 - 4K, <other> - 1K");
 		PrintAndLog("d - write keys to binary file\n");
 		PrintAndLog("t - write keys to emulator memory");
+		PrintAndLog("s - slow execute. timeout 1ms");
+		PrintAndLog("ss- very slow execute. timeout 5ms");
 		PrintAndLog("      sample: hf mf chk 0 A 1234567890ab keys.dic");
 		PrintAndLog("              hf mf chk *1 ? t");
 		PrintAndLog("              hf mf chk *1 ? d");
+		PrintAndLog("              hf mf chk *1 ? s");
+		PrintAndLog("              hf mf chk *1 ? dss");
 		return 0;
 	}
 
@@ -1042,42 +988,28 @@ int CmdHF14AMfChk(const char *Cmd)
 	int i, res;
 	int	keycnt = 0;
 	char ctmp	= 0x00;
+	char ctmp3[3]	= {0x00};
 	uint8_t blockNo = 0;
-	uint8_t SectorsCnt = 1;
+	uint8_t SectorsCnt = 0;
 	uint8_t keyType = 0;
 	uint64_t key64 = 0;
+	uint32_t timeout14a = 0; // timeout in us
+	bool param3InUse = false;
 
 	int transferToEml = 0;
 	int createDumpFile = 0;
+	
+	sector_t *e_sector = NULL;
 
 	keyBlock = calloc(stKeyBlock, 6);
 	if (keyBlock == NULL) return 1;
 
-	uint64_t defaultKeys[] =
-	{
-		0xffffffffffff, // Default key (first key used by program if no user defined key)
-		0x000000000000, // Blank key
-		0xa0a1a2a3a4a5, // NFCForum MAD key
-		0xb0b1b2b3b4b5,
-		0xaabbccddeeff,
-		0x4d3a99c351dd,
-		0x1a982c7e459a,
-		0xd3f7d3f7d3f7,
-		0x714c5c886e97,
-		0x587ee5f9350f,
-		0xa0478cc39091,
-		0x533cb6c723f6,
-		0x8fd0a4f256e9
-	};
-	int defaultKeysSize = sizeof(defaultKeys) / sizeof(uint64_t);
-
-	for (int defaultKeyCounter = 0; defaultKeyCounter < defaultKeysSize; defaultKeyCounter++)
-	{
-		num_to_bytes(defaultKeys[defaultKeyCounter], 6, (uint8_t*)(keyBlock + defaultKeyCounter * 6));
+	int defaultKeysSize = MifareDefaultKeysSize;
+	for (int defaultKeyCounter = 0; defaultKeyCounter < defaultKeysSize; defaultKeyCounter++){
+		num_to_bytes(MifareDefaultKeys[defaultKeyCounter], 6, (uint8_t*)(keyBlock + defaultKeyCounter * 6));
 	}
 
 	if (param_getchar(Cmd, 0)=='*') {
-		blockNo = 3;
 		SectorsCnt = ParamCardSizeSectors(param_getchar(Cmd + 1, 0));
 	}
 	else
@@ -1086,10 +1018,10 @@ int CmdHF14AMfChk(const char *Cmd)
 	ctmp = param_getchar(Cmd, 1);
 	switch (ctmp) {
 	case 'a': case 'A':
-		keyType = !0;
+		keyType = 0;
 		break;
 	case 'b': case 'B':
-		keyType = !1;
+		keyType = 1;
 		break;
 	case '?':
 		keyType = 2;
@@ -1100,11 +1032,33 @@ int CmdHF14AMfChk(const char *Cmd)
 		return 1;
 	};
 
+	// transfer to emulator & create dump file
 	ctmp = param_getchar(Cmd, 2);
-	if		(ctmp == 't' || ctmp == 'T') transferToEml = 1;
-	else if (ctmp == 'd' || ctmp == 'D') createDumpFile = 1;
+	if (ctmp == 't' || ctmp == 'T') transferToEml = 1;
+	if (ctmp == 'd' || ctmp == 'D') createDumpFile = 1;
+	
+	param3InUse = transferToEml | createDumpFile;
+	
+	timeout14a = 500; // fast by default
+	// double parameters - ts, ds
+	int clen = param_getlength(Cmd, 2);
+	if (clen == 2 || clen == 3){
+		param_getstr(Cmd, 2, ctmp3);
+		ctmp = ctmp3[1];
+	}
+	//parse
+	if (ctmp == 's' || ctmp == 'S') {
+		timeout14a = 1000; // slow
+		if (!param3InUse && clen == 2 && (ctmp3[1] == 's' || ctmp3[1] == 'S')) {
+			timeout14a = 5000; // very slow
+		}
+		if (param3InUse && clen == 3 && (ctmp3[2] == 's' || ctmp3[2] == 'S')) {
+			timeout14a = 5000; // very slow
+		}
+		param3InUse = true;
+	}
 
-	for (i = transferToEml || createDumpFile; param_getchar(Cmd, 2 + i); i++) {
+	for (i = param3InUse; param_getchar(Cmd, 2 + i); i++) {
 		if (!param_gethex(Cmd, 2 + i, keyBlock + 6 * keycnt, 12)) {
 			if ( stKeyBlock - keycnt < 2) {
 				p = realloc(keyBlock, 6*(stKeyBlock+=10));
@@ -1169,6 +1123,7 @@ int CmdHF14AMfChk(const char *Cmd)
 		}
 	}
 
+	// fill with default keys
 	if (keycnt == 0) {
 		PrintAndLog("No key specified, trying default keys");
 		for (;keycnt < defaultKeysSize; keycnt++)
@@ -1178,47 +1133,84 @@ int CmdHF14AMfChk(const char *Cmd)
 	}
 
 	// initialize storage for found keys
-	bool validKey[2][40];
-	uint8_t foundKey[2][40][6];
-	for (uint16_t t = 0; t < 2; t++) {
+	e_sector = calloc(SectorsCnt, sizeof(sector_t));
+	if (e_sector == NULL) return 1;
+	for (uint8_t keyAB = 0; keyAB < 2; keyAB++) {
 		for (uint16_t sectorNo = 0; sectorNo < SectorsCnt; sectorNo++) {
-			validKey[t][sectorNo] = false;
-			for (uint16_t i = 0; i < 6; i++) {
-				foundKey[t][sectorNo][i] = 0xff;
-			}
+			e_sector[sectorNo].Key[keyAB] = 0xffffffffffff;
+			e_sector[sectorNo].foundKey[keyAB] = 0;
 		}
 	}
+	printf("\n");
 
-	for ( int t = !keyType; t < 2; keyType==2?(t++):(t=2) ) {
-		int b=blockNo;
-		for (int i = 0; i < SectorsCnt; ++i) {
-			PrintAndLog("--sector:%2d, block:%3d, key type:%C, key count:%2d ", i, b, t?'B':'A', keycnt);
-			uint32_t max_keys = keycnt>USB_CMD_DATA_SIZE/6?USB_CMD_DATA_SIZE/6:keycnt;
+	bool foundAKey = false;
+	uint32_t max_keys = keycnt > USB_CMD_DATA_SIZE / 6 ? USB_CMD_DATA_SIZE / 6 : keycnt;
+	if (SectorsCnt) {
+		PrintAndLog("To cancel this operation press the button on the proxmark...");
+		printf("--");
+		for (uint32_t c = 0; c < keycnt; c += max_keys) {
+
+			uint32_t size = keycnt-c > max_keys ? max_keys : keycnt-c;
+			res = mfCheckKeysSec(SectorsCnt, keyType, timeout14a * 1.06 / 100, true, size, &keyBlock[6 * c], e_sector); // timeout is (ms * 106)/10 or us*0.0106
+
+			if (res != 1) {
+				if (!res) {
+					printf("o");
+					foundAKey = true;
+				} else {
+					printf(".");
+				}
+			} else {
+				printf("\n");
+				PrintAndLog("Command execute timeout");
+			}
+		}
+	} else {
+		int keyAB = keyType;
+		do {
 			for (uint32_t c = 0; c < keycnt; c+=max_keys) {
-				uint32_t size = keycnt-c>max_keys?max_keys:keycnt-c;
-				res = mfCheckKeys(b, t, true, size, &keyBlock[6*c], &key64);
+
+				uint32_t size = keycnt-c > max_keys ? max_keys : keycnt-c;
+				res = mfCheckKeys(blockNo, keyAB & 0x01, true, size, &keyBlock[6 * c], &key64); 
+
 				if (res != 1) {
 					if (!res) {
-						PrintAndLog("Found valid key:[%012" PRIx64 "]",key64);
-						num_to_bytes(key64, 6, foundKey[t][i]);
-						validKey[t][i] = true;
+						PrintAndLog("Found valid key:[%d:%c]%012" PRIx64, blockNo, (keyAB & 0x01)?'B':'A', key64);
+						foundAKey = true;
 					}
 				} else {
 					PrintAndLog("Command execute timeout");
 				}
 			}
-			b<127?(b+=4):(b+=16);
-		}
+		} while(--keyAB > 0);
 	}
-
+	
+	// print result
+	if (foundAKey) {
+		if (SectorsCnt) {
+			PrintAndLog("");
+			PrintAndLog("|---|----------------|---|----------------|---|");
+			PrintAndLog("|sec|key A           |res|key B           |res|");
+			PrintAndLog("|---|----------------|---|----------------|---|");
+			for (i = 0; i < SectorsCnt; i++) {
+				PrintAndLog("|%03d|  %012" PRIx64 "  | %d |  %012" PRIx64 "  | %d |", i,
+					e_sector[i].Key[0], e_sector[i].foundKey[0], e_sector[i].Key[1], e_sector[i].foundKey[1]);
+			}
+			PrintAndLog("|---|----------------|---|----------------|---|");
+		}
+	} else {
+		PrintAndLog("");
+		PrintAndLog("No valid keys found.");
+	}	
+	
 	if (transferToEml) {
 		uint8_t block[16];
 		for (uint16_t sectorNo = 0; sectorNo < SectorsCnt; sectorNo++) {
-			if (validKey[0][sectorNo] || validKey[1][sectorNo]) {
+			if (e_sector[sectorNo].foundKey[0] || e_sector[sectorNo].foundKey[1]) {
 				mfEmlGetMem(block, FirstBlockOfSector(sectorNo) + NumBlocksPerSector(sectorNo) - 1, 1);
 				for (uint16_t t = 0; t < 2; t++) {
-					if (validKey[t][sectorNo]) {
-						memcpy(block + t*10, foundKey[t][sectorNo], 6);
+					if (e_sector[sectorNo].foundKey[t]) {
+						num_to_bytes(e_sector[sectorNo].Key[t], 6, block + t * 10);
 					}
 				}
 				mfEmlSetMem(block, FirstBlockOfSector(sectorNo) + NumBlocksPerSector(sectorNo) - 1, 1);
@@ -1231,16 +1223,22 @@ int CmdHF14AMfChk(const char *Cmd)
 		FILE *fkeys = fopen("dumpkeys.bin","wb");
 		if (fkeys == NULL) {
 			PrintAndLog("Could not create file dumpkeys.bin");
+			free(e_sector);
 			free(keyBlock);
 			return 1;
 		}
-		for (uint16_t t = 0; t < 2; t++) {
-			fwrite(foundKey[t], 1, 6*SectorsCnt, fkeys);
+		uint8_t mkey[6];
+		for (uint8_t t = 0; t < 2; t++) {
+			for (uint8_t sectorNo = 0; sectorNo < SectorsCnt; sectorNo++) {
+				num_to_bytes(e_sector[sectorNo].Key[t], 6, mkey);
+				fwrite(mkey, 1, 6, fkeys);
+			}
 		}
 		fclose(fkeys);
 		PrintAndLog("Found keys have been dumped to file dumpkeys.bin. 0xffffffffffff has been inserted for unknown keys.");
 	}
 
+	free(e_sector);
 	free(keyBlock);
 	PrintAndLog("");
 	return 0;
diff --git a/client/cmdhfmf.h b/client/cmdhfmf.h
index 235fd86d..3bd3e95a 100644
--- a/client/cmdhfmf.h
+++ b/client/cmdhfmf.h
@@ -11,6 +11,8 @@
 #ifndef CMDHFMF_H__
 #define CMDHFMF_H__
 
+#include "mifaredefault.h"
+
 extern int CmdHFMF(const char *Cmd);
 
 extern int CmdHF14AMfDbg(const char* cmd);
diff --git a/client/cmdmain.c b/client/cmdmain.c
index f407cee4..db88b3ac 100644
--- a/client/cmdmain.c
+++ b/client/cmdmain.c
@@ -139,7 +139,7 @@ int getCommand(UsbCommand* response)
  * @param ms_timeout
  * @return true if command was returned, otherwise false
  */
-bool WaitForResponseTimeout(uint32_t cmd, UsbCommand* response, size_t ms_timeout) {
+bool WaitForResponseTimeoutW(uint32_t cmd, UsbCommand* response, size_t ms_timeout, bool show_warning) {
   
 	UsbCommand resp;
 	
@@ -155,7 +155,7 @@ bool WaitForResponseTimeout(uint32_t cmd, UsbCommand* response, size_t ms_timeou
 			}
 		}
 		msleep(10); // XXX ugh
-		if (dm_seconds == 200) { // Two seconds elapsed
+		if (dm_seconds == 200 && show_warning) { // Two seconds elapsed
 			PrintAndLog("Waiting for a response from the proxmark...");
 			PrintAndLog("Don't forget to cancel its operation first by pressing on the button");
 		}
@@ -163,9 +163,12 @@ bool WaitForResponseTimeout(uint32_t cmd, UsbCommand* response, size_t ms_timeou
 	return false;
 }
 
+bool WaitForResponseTimeout(uint32_t cmd, UsbCommand* response, size_t ms_timeout) {
+	return WaitForResponseTimeoutW(cmd, response, ms_timeout, true);
+}
 
 bool WaitForResponse(uint32_t cmd, UsbCommand* response) {
-	return WaitForResponseTimeout(cmd,response,-1);
+	return WaitForResponseTimeoutW(cmd, response, -1, true);
 }
 
 
diff --git a/client/cmdmain.h b/client/cmdmain.h
index 0de3f392..d39bc114 100644
--- a/client/cmdmain.h
+++ b/client/cmdmain.h
@@ -18,6 +18,7 @@
 
 extern void UsbCommandReceived(UsbCommand *UC);
 extern int CommandReceived(char *Cmd);
+extern bool WaitForResponseTimeoutW(uint32_t cmd, UsbCommand* response, size_t ms_timeout, bool show_warning);
 extern bool WaitForResponseTimeout(uint32_t cmd, UsbCommand* response, size_t ms_timeout);
 extern bool WaitForResponse(uint32_t cmd, UsbCommand* response);
 extern void clearCommandBuffer();
diff --git a/client/mifaredefault.h b/client/mifaredefault.h
new file mode 100644
index 00000000..78231c86
--- /dev/null
+++ b/client/mifaredefault.h
@@ -0,0 +1,40 @@
+//-----------------------------------------------------------------------------
+// Copyright (C) 2017 Merlok
+//
+// This code is licensed to you under the terms of the GNU GPL, version 2 or,
+// at your option, any later version. See the LICENSE.txt file for the text of
+// the license.
+//-----------------------------------------------------------------------------
+// Mifare default constants
+//-----------------------------------------------------------------------------
+
+#ifndef MIFAREDEFAULT_H__
+#define MIFAREDEFAULT_H__
+
+#include <inttypes.h>
+
+#define MifareDefaultKeysSize sizeof(MifareDefaultKeys) / sizeof(uint64_t)
+
+static const uint64_t MifareDefaultKeys[] =
+{
+	0xffffffffffff, // Default key (first key used by program if no user defined key)
+	0x000000000000, // Blank key
+	0xa0a1a2a3a4a5, // NFCForum MAD key
+	0xb0b1b2b3b4b5,
+	0xaabbccddeeff,
+	0x1a2b3c4d5e6f,
+	0x123456789abc,
+	0x010203040506,
+	0x123456abcdef,
+	0xabcdef123456,
+	0x4d3a99c351dd,
+	0x1a982c7e459a,
+	0xd3f7d3f7d3f7,
+	0x714c5c886e97,
+	0x587ee5f9350f,
+	0xa0478cc39091,
+	0x533cb6c723f6,
+	0x8fd0a4f256e9
+};
+
+#endif
diff --git a/client/mifarehost.c b/client/mifarehost.c
index 629c8feb..a02019a3 100644
--- a/client/mifarehost.c
+++ b/client/mifarehost.c
@@ -228,17 +228,46 @@ int mfCheckKeys (uint8_t blockNo, uint8_t keyType, bool clear_trace, uint8_t key
 
 	*key = -1;
 
-	UsbCommand c = {CMD_MIFARE_CHKKEYS, {((blockNo & 0xff) | ((keyType&0xff)<<8)), clear_trace, keycnt}};
+	UsbCommand c = {CMD_MIFARE_CHKKEYS, {((blockNo & 0xff) | ((keyType & 0xff) << 8)), clear_trace, keycnt}}; 
 	memcpy(c.d.asBytes, keyBlock, 6 * keycnt);
 	SendCommand(&c);
 
 	UsbCommand resp;
-	if (!WaitForResponseTimeout(CMD_ACK,&resp,3000)) return 1;
+	if (!WaitForResponseTimeout(CMD_ACK,&resp,3000)) return 1; 
 	if ((resp.arg[0] & 0xff) != 0x01) return 2;
 	*key = bytes_to_num(resp.d.asBytes, 6);
 	return 0;
 }
 
+int mfCheckKeysSec(uint8_t sectorCnt, uint8_t keyType, uint8_t timeout14a, bool clear_trace, uint8_t keycnt, uint8_t * keyBlock, sector_t * e_sector){
+
+	uint8_t keyPtr = 0;
+
+	if (e_sector == NULL)
+		return -1;
+
+	UsbCommand c = {CMD_MIFARE_CHKKEYS, {((sectorCnt & 0xff) | ((keyType & 0xff) << 8)), (clear_trace | 0x02)|((timeout14a & 0xff) << 8), keycnt}}; 
+	memcpy(c.d.asBytes, keyBlock, 6 * keycnt);
+	SendCommand(&c);
+
+	UsbCommand resp;
+	if (!WaitForResponseTimeoutW(CMD_ACK, &resp, MAX(3000, 1000 + 13 * sectorCnt * keycnt * (keyType == 2 ? 2 : 1)), false)) return 1; // timeout: 13 ms / fail auth
+	if ((resp.arg[0] & 0xff) != 0x01) return 2;
+	
+	bool foundAKey = false;
+	for(int sec = 0; sec < sectorCnt; sec++){
+		for(int keyAB = 0; keyAB < 2; keyAB++){
+			keyPtr = *(resp.d.asBytes + keyAB * 40 + sec);
+			if (keyPtr){
+				e_sector[sec].foundKey[keyAB] = true;
+				e_sector[sec].Key[keyAB] = bytes_to_num(keyBlock + (keyPtr - 1) * 6, 6);
+				foundAKey = true;
+			}
+		}
+	}
+	return foundAKey ? 0 : 3;
+}
+
 // Compare 16 Bits out of cryptostate
 int Compare16Bits(const void * a, const void * b) {
 	if ((*(uint64_t*)b & 0x00ff000000ff0000) == (*(uint64_t*)a & 0x00ff000000ff0000)) return 0;
diff --git a/client/mifarehost.h b/client/mifarehost.h
index 34793a29..118d55cc 100644
--- a/client/mifarehost.h
+++ b/client/mifarehost.h
@@ -1,4 +1,4 @@
-// Merlok, 2011
+// Merlok, 2011, 2017
 // people from mifare@nethemba.com, 2010
 //
 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
@@ -15,6 +15,11 @@
 #include <stdbool.h>
 #include "data.h"
 
+// defaults
+// timeout in units. (ms * 106)/10 or us*0.0106
+// 5 == 500us
+#define MF_CHKKEYS_DEFTIMEOUT		5
+
 // mfCSetBlock work flags
 #define CSETBLOCK_UID 				0x01
 #define CSETBLOCK_WUPC				0x02
@@ -24,11 +29,17 @@
 #define CSETBLOCK_SINGLE_OPER			0x1F
 #define CSETBLOCK_MAGIC_1B 			0x40
 
+typedef struct {
+	uint64_t Key[2];
+	int foundKey[2];
+} sector_t;
+
 extern char logHexFileName[FILE_PATH_SIZE];
 
 extern int mfDarkside(uint64_t *key);
 extern int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t *key, uint8_t trgBlockNo, uint8_t trgKeyType, uint8_t *ResultKeys, bool calibrate);
 extern int mfCheckKeys (uint8_t blockNo, uint8_t keyType, bool clear_trace, uint8_t keycnt, uint8_t *keyBlock, uint64_t *key);
+extern int mfCheckKeysSec(uint8_t sectorCnt, uint8_t keyType, uint8_t timeout14a, bool clear_trace, uint8_t keycnt, uint8_t * keyBlock, sector_t * e_sector);
 
 extern int mfEmlGetMem(uint8_t *data, int blockNum, int blocksCount);
 extern int mfEmlSetMem(uint8_t *data, int blockNum, int blocksCount);
diff --git a/common/usb_cdc.c b/common/usb_cdc.c
index 84aa2c06..56690ad8 100644
--- a/common/usb_cdc.c
+++ b/common/usb_cdc.c
@@ -38,19 +38,20 @@
 
 
 #define AT91C_EP_CONTROL     0
-#define AT91C_EP_IN_SIZE  0x40
 #define AT91C_EP_OUT         1
-#define AT91C_EP_OUT_SIZE 0x40
 #define AT91C_EP_IN          2
+#define AT91C_EP_NOTIFY      3
+#define AT91C_EP_OUT_SIZE 0x40
+#define AT91C_EP_IN_SIZE  0x40
 
 static const char devDescriptor[] = {
 	/* Device descriptor */
 	0x12,      // bLength
 	0x01,      // bDescriptorType
 	0x00,0x02, // Complies with USB Spec. Release (0200h = release 2.0)
-	0x02,      // bDeviceClass:    CDC class code
-	0x00,      // bDeviceSubclass: CDC class sub code
-	0x00,      // bDeviceProtocol: CDC Device protocol
+	0x02,      // bDeviceClass:    (Communication Device Class)
+	0x00,      // bDeviceSubclass: (unused at this time)
+	0x00,      // bDeviceProtocol: (unused at this time)
 	0x08,      // bMaxPacketSize0
 	0xc4,0x9a, // Vendor ID (0x9ac4 = J. Westhues)
 	0x8f,0x4b, // Product ID (0x4b8f = Proxmark-3 RFID Instrument)
@@ -74,79 +75,78 @@ static const char cfgDescriptor[] = {
 	0xC0,   // CbmAttributes 0xA0
 	0xFA,   // CMaxPower
 
-	/* Communication Class Interface Descriptor Requirement */
+	/* Interface 0 Descriptor: Communication Class Interface */
 	0x09, // bLength
 	0x04, // bDescriptorType
 	0x00, // bInterfaceNumber
 	0x00, // bAlternateSetting
 	0x01, // bNumEndpoints
-	0x02, // bInterfaceClass
-	0x02, // bInterfaceSubclass
-	0x01, // bInterfaceProtocol
+	0x02, // bInterfaceClass:       Communication Interface Class
+	0x02, // bInterfaceSubclass:    Abstract Control Model
+	0x01, // bInterfaceProtocol:    Common AT Commands, V.25ter
 	0x00, // iInterface
 
 	/* Header Functional Descriptor */
 	0x05, // bFunction Length
-	0x24, // bDescriptor type: CS_INTERFACE
-	0x00, // bDescriptor subtype: Header Func Desc
+	0x24, // bDescriptor type:      CS_INTERFACE
+	0x00, // bDescriptor subtype:   Header Functional Descriptor
 	0x10, // bcdCDC:1.1
 	0x01,
 
 	/* ACM Functional Descriptor */
 	0x04, // bFunctionLength
-	0x24, // bDescriptor Type: CS_INTERFACE
-	0x02, // bDescriptor Subtype: ACM Func Desc
-	0x02, // bmCapabilities
+	0x24, // bDescriptor Type:      CS_INTERFACE
+	0x02, // bDescriptor Subtype:   Abstract Control Management Functional Descriptor
+	0x02, // bmCapabilities:        D1: Device supports the request combination of Set_Line_Coding, Set_Control_Line_State, Get_Line_Coding, and the notification Serial_State
 
 	/* Union Functional Descriptor */
 	0x05, // bFunctionLength
-	0x24, // bDescriptorType: CS_INTERFACE
-	0x06, // bDescriptor Subtype: Union Func Desc
-	0x00, // bMasterInterface: Communication Class Interface
-	0x01, // bSlaveInterface0: Data Class Interface
+	0x24, // bDescriptorType:       CS_INTERFACE
+	0x06, // bDescriptor Subtype:   Union Functional Descriptor
+	0x00, // bMasterInterface:      Communication Class Interface
+	0x01, // bSlaveInterface0:      Data Class Interface
 
 	/* Call Management Functional Descriptor */
 	0x05, // bFunctionLength
-	0x24, // bDescriptor Type: CS_INTERFACE
-	0x01, // bDescriptor Subtype: Call Management Func Desc
-	0x00, // bmCapabilities: D1 + D0
-	0x01, // bDataInterface: Data Class Interface 1
+	0x24, // bDescriptor Type:      CS_INTERFACE
+	0x01, // bDescriptor Subtype:   Call Management Functional Descriptor
+	0x00, // bmCapabilities:        Device sends/receives call management information only over the Communication Class interface. Device does not handle call management itself
+	0x01, // bDataInterface:        Data Class Interface 1
 
 	/* Endpoint 1 descriptor */
 	0x07,   // bLength
 	0x05,   // bDescriptorType
-	0x83,   // bEndpointAddress, Endpoint 03 - IN
-	0x03,   // bmAttributes      INT
-	0x08,   // wMaxPacketSize
+	0x83,   // bEndpointAddress:    Endpoint 03 - IN
+	0x03,   // bmAttributes:        INT
+	0x08,   // wMaxPacketSize:      8
 	0x00,
 	0xFF,   // bInterval
 
-	/* Data Class Interface Descriptor Requirement */
+	/* Interface 1 Descriptor: Data Class Interface */
 	0x09, // bLength
 	0x04, // bDescriptorType
 	0x01, // bInterfaceNumber
 	0x00, // bAlternateSetting
 	0x02, // bNumEndpoints
-	0x0A, // bInterfaceClass
-	0x00, // bInterfaceSubclass
-	0x00, // bInterfaceProtocol
+	0x0A, // bInterfaceClass:       Data Interface Class
+	0x00, // bInterfaceSubclass:    not used
+	0x00, // bInterfaceProtocol:    No class specific protocol required)
 	0x00, // iInterface
 
-	/* First alternate setting */
 	/* Endpoint 1 descriptor */
 	0x07,   // bLength
 	0x05,   // bDescriptorType
-	0x01,   // bEndpointAddress, Endpoint 01 - OUT
-	0x02,   // bmAttributes      BULK
-	AT91C_EP_OUT_SIZE,   // wMaxPacketSize
+	0x01,   // bEndpointAddress:    Endpoint 01 - OUT
+	0x02,   // bmAttributes:        BULK
+	AT91C_EP_OUT_SIZE, // wMaxPacketSize
 	0x00,
 	0x00,   // bInterval
 
 	/* Endpoint 2 descriptor */
 	0x07,   // bLength
 	0x05,   // bDescriptorType
-	0x82,   // bEndpointAddress, Endpoint 02 - IN
-	0x02,   // bmAttributes      BULK
+	0x82,   // bEndpointAddress:    Endpoint 02 - IN
+	0x02,   // bmAttributes:        BULK
 	AT91C_EP_IN_SIZE,   // wMaxPacketSize
 	0x00,
 	0x00    // bInterval
@@ -262,6 +262,7 @@ AT91S_CDC_LINE_CODING line = {
 	0,      // None Parity
 	8};     // 8 Data bits
 
+
 void AT91F_CDC_Enumerate();
 
 AT91PS_UDP pUdp = AT91C_BASE_UDP;
@@ -269,52 +270,55 @@ byte_t btConfiguration = 0;
 byte_t btConnection    = 0;
 byte_t btReceiveBank   = AT91C_UDP_RX_DATA_BK0;
 
+
 //*----------------------------------------------------------------------------
 //* \fn    usb_disable
 //* \brief This function deactivates the USB device
 //*----------------------------------------------------------------------------
 void usb_disable() {
-  // Disconnect the USB device
-  AT91C_BASE_PIOA->PIO_ODR = GPIO_USB_PU;
-  
-  // Clear all lingering interrupts
-  if(pUdp->UDP_ISR & AT91C_UDP_ENDBUSRES) {
-    pUdp->UDP_ICR = AT91C_UDP_ENDBUSRES;
-  }
+	// Disconnect the USB device
+	AT91C_BASE_PIOA->PIO_ODR = GPIO_USB_PU;
+
+	// Clear all lingering interrupts
+	if(pUdp->UDP_ISR & AT91C_UDP_ENDBUSRES) {
+		pUdp->UDP_ICR = AT91C_UDP_ENDBUSRES;
+	}
 }
 
+
 //*----------------------------------------------------------------------------
 //* \fn    usb_enable
 //* \brief This function Activates the USB device
 //*----------------------------------------------------------------------------
 void usb_enable() {
-  // Set the PLL USB Divider
-  AT91C_BASE_CKGR->CKGR_PLLR |= AT91C_CKGR_USBDIV_1 ;
-  
-  // Specific Chip USB Initialisation
-  // Enables the 48MHz USB clock UDPCK and System Peripheral USB Clock
-  AT91C_BASE_PMC->PMC_SCER = AT91C_PMC_UDP;
-  AT91C_BASE_PMC->PMC_PCER = (1 << AT91C_ID_UDP);
-  
-  // Enable UDP PullUp (USB_DP_PUP) : enable & Clear of the corresponding PIO
-  // Set in PIO mode and Configure in Output
-  AT91C_BASE_PIOA->PIO_PER = GPIO_USB_PU; // Set in PIO mode
-	AT91C_BASE_PIOA->PIO_OER = GPIO_USB_PU; // Configure as Output
-  
-  // Clear for set the Pullup resistor
-	AT91C_BASE_PIOA->PIO_CODR = GPIO_USB_PU;
-  
-  // Disconnect and reconnect USB controller for 100ms
-  usb_disable();
-  
-  // Wait for a short while
-  for (volatile size_t i=0; i<0x100000; i++);
+	// Set the PLL USB Divider
+	AT91C_BASE_CKGR->CKGR_PLLR |= AT91C_CKGR_USBDIV_1 ;
 
-  // Reconnect USB reconnect
-  AT91C_BASE_PIOA->PIO_SODR = GPIO_USB_PU;
-  AT91C_BASE_PIOA->PIO_OER = GPIO_USB_PU;
+	// Specific Chip USB Initialisation
+	// Enables the 48MHz USB clock UDPCK and System Peripheral USB Clock
+	AT91C_BASE_PMC->PMC_SCER = AT91C_PMC_UDP;
+	AT91C_BASE_PMC->PMC_PCER = (1 << AT91C_ID_UDP);
+
+	// Enable UDP PullUp (USB_DP_PUP) : enable & Clear of the corresponding PIO
+	// Set in PIO mode and Configure in Output
+	AT91C_BASE_PIOA->PIO_PER = GPIO_USB_PU; // Set in PIO mode
+	AT91C_BASE_PIOA->PIO_OER = GPIO_USB_PU; // Configure as Output
+
+	// Clear for set the Pullup resistor
+	AT91C_BASE_PIOA->PIO_CODR = GPIO_USB_PU;
+
+	// Disconnect and reconnect USB controller for 100ms
+	usb_disable();
+
+	// Wait for a short while
+	for (volatile size_t i=0; i<0x100000; i++);
+
+	// Reconnect USB reconnect
+	AT91C_BASE_PIOA->PIO_SODR = GPIO_USB_PU;
+	AT91C_BASE_PIOA->PIO_OER = GPIO_USB_PU;
 }
 
+
 //*----------------------------------------------------------------------------
 //* \fn    usb_check
 //* \brief Test if the device is configured and handle enumeration
@@ -331,8 +335,7 @@ bool usb_check() {
 		pUdp->UDP_FADDR = AT91C_UDP_FEN;
 		// Configure endpoint 0
 		pUdp->UDP_CSR[AT91C_EP_CONTROL] = (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_CTRL);
-	}
-	else if (isr & AT91C_UDP_EPINT0) {
+	} else if (isr & AT91C_UDP_EPINT0) {
 		pUdp->UDP_ICR = AT91C_UDP_EPINT0;
 		AT91F_CDC_Enumerate();
 	}
@@ -342,10 +345,11 @@ bool usb_check() {
 
 bool usb_poll()
 {
-  if (!usb_check()) return false;
-  return (pUdp->UDP_CSR[AT91C_EP_OUT] & btReceiveBank);
+	if (!usb_check()) return false;
+	return (pUdp->UDP_CSR[AT91C_EP_OUT] & btReceiveBank);
 }
 
+
 /**
 	In github PR #129, some users appears to get a false positive from
 	usb_poll, which returns true, but the usb_read operation
@@ -356,7 +360,6 @@ bool usb_poll()
 **/
 bool usb_poll_validate_length()
 {
-
 	if (!usb_check()) return false;
 	if (!(pUdp->UDP_CSR[AT91C_EP_OUT] & btReceiveBank)) return false;
 	return (pUdp->UDP_CSR[AT91C_EP_OUT] >> 16) >  0;
@@ -393,48 +396,54 @@ uint32_t usb_read(byte_t* data, size_t len) {
 	return nbBytesRcv;
 }
 
+
 //*----------------------------------------------------------------------------
 //* \fn    usb_write
 //* \brief Send through endpoint 2
 //*----------------------------------------------------------------------------
 uint32_t usb_write(const byte_t* data, const size_t len) {
-  size_t length = len;
+	size_t length = len;
 	uint32_t cpt = 0;
 
-  if (!length) return 0;
-  if (!usb_check()) return 0;
-  
+	if (!length) return 0;
+	if (!usb_check()) return 0;
+
 	// Send the first packet
-	cpt = MIN(length, AT91C_EP_IN_SIZE-1);
+	cpt = MIN(length, AT91C_EP_IN_SIZE);
 	length -= cpt;
-	while (cpt--) pUdp->UDP_FDR[AT91C_EP_IN] = *data++;
+	while (cpt--) {
+		pUdp->UDP_FDR[AT91C_EP_IN] = *data++;
+	}
 	UDP_SET_EP_FLAGS(AT91C_EP_IN, AT91C_UDP_TXPKTRDY);
 
 	while (length) {
-		// Fill the second bank
-		cpt = MIN(length, AT91C_EP_IN_SIZE-1);
+		// Fill the next bank
+		cpt = MIN(length, AT91C_EP_IN_SIZE);
 		length -= cpt;
-		while (cpt--) pUdp->UDP_FDR[AT91C_EP_IN] = *data++;
-		// Wait for the first bank to be sent
+		while (cpt--) {
+			pUdp->UDP_FDR[AT91C_EP_IN] = *data++;
+		}
+		// Wait for the previous bank to be sent
 		while (!(pUdp->UDP_CSR[AT91C_EP_IN] & AT91C_UDP_TXCOMP)) {
 			if (!usb_check()) return length;
-    }
+		}
 		UDP_CLEAR_EP_FLAGS(AT91C_EP_IN, AT91C_UDP_TXCOMP);
 		while (pUdp->UDP_CSR[AT91C_EP_IN] & AT91C_UDP_TXCOMP);
 		UDP_SET_EP_FLAGS(AT91C_EP_IN, AT91C_UDP_TXPKTRDY);
 	}
-  
+
 	// Wait for the end of transfer
 	while (!(pUdp->UDP_CSR[AT91C_EP_IN] & AT91C_UDP_TXCOMP)) {
 		if (!usb_check()) return length;
-  }
-  
+	}
+
 	UDP_CLEAR_EP_FLAGS(AT91C_EP_IN, AT91C_UDP_TXCOMP);
 	while (pUdp->UDP_CSR[AT91C_EP_IN] & AT91C_UDP_TXCOMP);
 
 	return length;
 }
 
+
 //*----------------------------------------------------------------------------
 //* \fn    AT91F_USB_SendData
 //* \brief Send Data through the control endpoint
@@ -477,6 +486,7 @@ static void AT91F_USB_SendData(AT91PS_UDP pUdp, const char *pData, uint32_t leng
 	}
 }
 
+
 //*----------------------------------------------------------------------------
 //* \fn    AT91F_USB_SendZlp
 //* \brief Send zero length packet through the control endpoint
@@ -488,6 +498,7 @@ void AT91F_USB_SendZlp(AT91PS_UDP pUdp) {
 	while (pUdp->UDP_CSR[AT91C_EP_CONTROL] & AT91C_UDP_TXCOMP);
 }
 
+
 //*----------------------------------------------------------------------------
 //* \fn    AT91F_USB_SendStall
 //* \brief Stall the control endpoint
@@ -499,6 +510,7 @@ void AT91F_USB_SendStall(AT91PS_UDP pUdp) {
 	while (pUdp->UDP_CSR[AT91C_EP_CONTROL] & (AT91C_UDP_FORCESTALL | AT91C_UDP_ISOERROR));
 }
 
+
 //*----------------------------------------------------------------------------
 //* \fn    AT91F_CDC_Enumerate
 //* \brief This function is a callback invoked when a SETUP packet is received
@@ -510,16 +522,16 @@ void AT91F_CDC_Enumerate() {
 	if ( !(pUdp->UDP_CSR[AT91C_EP_CONTROL] & AT91C_UDP_RXSETUP) )
 		return;
 
-	bmRequestType = pUdp->UDP_FDR[0];
-	bRequest      = pUdp->UDP_FDR[0];
-	wValue        = (pUdp->UDP_FDR[0] & 0xFF);
-	wValue       |= (pUdp->UDP_FDR[0] << 8);
-	wIndex        = (pUdp->UDP_FDR[0] & 0xFF);
-	wIndex       |= (pUdp->UDP_FDR[0] << 8);
-	wLength       = (pUdp->UDP_FDR[0] & 0xFF);
-	wLength      |= (pUdp->UDP_FDR[0] << 8);
+	bmRequestType = pUdp->UDP_FDR[AT91C_EP_CONTROL];
+	bRequest      = pUdp->UDP_FDR[AT91C_EP_CONTROL];
+	wValue        = (pUdp->UDP_FDR[AT91C_EP_CONTROL] & 0xFF);
+	wValue       |= (pUdp->UDP_FDR[AT91C_EP_CONTROL] << 8);
+	wIndex        = (pUdp->UDP_FDR[AT91C_EP_CONTROL] & 0xFF);
+	wIndex       |= (pUdp->UDP_FDR[AT91C_EP_CONTROL] << 8);
+	wLength       = (pUdp->UDP_FDR[AT91C_EP_CONTROL] & 0xFF);
+	wLength      |= (pUdp->UDP_FDR[AT91C_EP_CONTROL] << 8);
 
-	if (bmRequestType & 0x80) {
+	if (bmRequestType & 0x80) {	// Data Phase Transfer Direction Device to Host
 		UDP_SET_EP_FLAGS(AT91C_EP_CONTROL, AT91C_UDP_DIR);
 		while ( !(pUdp->UDP_CSR[AT91C_EP_CONTROL] & AT91C_UDP_DIR) );
 	}
@@ -553,29 +565,29 @@ void AT91F_CDC_Enumerate() {
 		btConfiguration = wValue;
 		AT91F_USB_SendZlp(pUdp);
 		pUdp->UDP_GLBSTATE  = (wValue) ? AT91C_UDP_CONFG : AT91C_UDP_FADDEN;
-		pUdp->UDP_CSR[1] = (wValue) ? (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_BULK_OUT) : 0;
-		pUdp->UDP_CSR[2] = (wValue) ? (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_BULK_IN)  : 0;
-		pUdp->UDP_CSR[3] = (wValue) ? (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_INT_IN)   : 0;
+		pUdp->UDP_CSR[AT91C_EP_OUT]    = (wValue) ? (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_BULK_OUT) : 0;
+		pUdp->UDP_CSR[AT91C_EP_IN]     = (wValue) ? (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_BULK_IN)  : 0;
+		pUdp->UDP_CSR[AT91C_EP_NOTIFY] = (wValue) ? (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_INT_IN)   : 0;
 		break;
 	case STD_GET_CONFIGURATION:
 		AT91F_USB_SendData(pUdp, (char *) &(btConfiguration), sizeof(btConfiguration));
 		break;
 	case STD_GET_STATUS_ZERO:
-		wStatus = 0;
+		wStatus = 0;	// Device is Bus powered, remote wakeup disabled
 		AT91F_USB_SendData(pUdp, (char *) &wStatus, sizeof(wStatus));
 		break;
 	case STD_GET_STATUS_INTERFACE:
-		wStatus = 0;
+		wStatus = 0; 	// reserved for future use
 		AT91F_USB_SendData(pUdp, (char *) &wStatus, sizeof(wStatus));
 		break;
 	case STD_GET_STATUS_ENDPOINT:
 		wStatus = 0;
 		wIndex &= 0x0F;
-		if ((pUdp->UDP_GLBSTATE & AT91C_UDP_CONFG) && (wIndex <= 3)) {
+		if ((pUdp->UDP_GLBSTATE & AT91C_UDP_CONFG) && (wIndex <= AT91C_EP_NOTIFY)) {
 			wStatus = (pUdp->UDP_CSR[wIndex] & AT91C_UDP_EPEDS) ? 0 : 1;
 			AT91F_USB_SendData(pUdp, (char *) &wStatus, sizeof(wStatus));
 		}
-		else if ((pUdp->UDP_GLBSTATE & AT91C_UDP_FADDEN) && (wIndex == 0)) {
+		else if ((pUdp->UDP_GLBSTATE & AT91C_UDP_FADDEN) && (wIndex == AT91C_EP_CONTROL)) {
 			wStatus = (pUdp->UDP_CSR[wIndex] & AT91C_UDP_EPEDS) ? 0 : 1;
 			AT91F_USB_SendData(pUdp, (char *) &wStatus, sizeof(wStatus));
 		}
@@ -590,7 +602,7 @@ void AT91F_CDC_Enumerate() {
 		break;
 	case STD_SET_FEATURE_ENDPOINT:
 		wIndex &= 0x0F;
-		if ((wValue == 0) && wIndex && (wIndex <= 3)) {
+		if ((wValue == 0) && (wIndex >= AT91C_EP_OUT) && (wIndex <= AT91C_EP_NOTIFY)) {
 			pUdp->UDP_CSR[wIndex] = 0;
 			AT91F_USB_SendZlp(pUdp);
 		}
@@ -605,13 +617,13 @@ void AT91F_CDC_Enumerate() {
 		break;
 	case STD_CLEAR_FEATURE_ENDPOINT:
 		wIndex &= 0x0F;
-		if ((wValue == 0) && wIndex && (wIndex <= 3)) {
-			if (wIndex == 1)
-				pUdp->UDP_CSR[1] = (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_BULK_OUT);
-			else if (wIndex == 2)
-				pUdp->UDP_CSR[2] = (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_BULK_IN);
-			else if (wIndex == 3)
-				pUdp->UDP_CSR[3] = (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_ISO_IN);
+		if ((wValue == 0) && (wIndex >= AT91C_EP_OUT) && (wIndex <= AT91C_EP_NOTIFY)) {
+			if (wIndex == AT91C_EP_OUT)
+				pUdp->UDP_CSR[AT91C_EP_OUT] = (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_BULK_OUT);
+			else if (wIndex == AT91C_EP_IN)
+				pUdp->UDP_CSR[AT91C_EP_IN] = (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_BULK_IN);
+			else if (wIndex == AT91C_EP_NOTIFY)
+				pUdp->UDP_CSR[AT91C_EP_NOTIFY] = (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_INT_IN);
 			AT91F_USB_SendZlp(pUdp);
 		}
 		else