diff --git a/src/altera.cpp b/src/altera.cpp
index 0415725..51d7ec2 100644
--- a/src/altera.cpp
+++ b/src/altera.cpp
@@ -101,7 +101,7 @@ void Altera::programMem(RawParser &_bit)
 
 	int xfer_len = 512;
 	int tx_len;
-	int tx_end;
+	Jtag::tapState_t tx_end;
 
 	for (int i=0; i < byte_length; i+=xfer_len) {
 		if (i + xfer_len > byte_length) {  // last packet with some size
@@ -352,7 +352,7 @@ void Altera::shiftVIR(uint32_t reg)
 }
 
 void Altera::shiftVDR(uint8_t * tx, uint8_t * rx, uint32_t len,
-		int end_state, bool debug)
+		Jtag::tapState_t end_state, bool debug)
 {
 	(void) debug;
 	uint8_t tx_ir[2] = {USER0, 0};
diff --git a/src/altera.hpp b/src/altera.hpp
index 1c359d0..1e40aa9 100644
--- a/src/altera.hpp
+++ b/src/altera.hpp
@@ -98,7 +98,7 @@ class Altera: public Device, SPIInterface {
 		 * \param[in] end_state: next state at the end of xfer
 		 */
 		void shiftVDR(uint8_t * tx, uint8_t * rx, uint32_t len,
-				int end_state = Jtag::UPDATE_DR, bool debug = false);
+				Jtag::tapState_t end_state = Jtag::UPDATE_DR, bool debug = false);
 
 		std::string _device_package;
 		std::string _spiOverJtagPath; /**< spiOverJtag explicit path */
diff --git a/src/anlogic.cpp b/src/anlogic.cpp
index 19856c8..f70314b 100644
--- a/src/anlogic.cpp
+++ b/src/anlogic.cpp
@@ -113,7 +113,7 @@ void Anlogic::program(unsigned int offset, bool unprotect_flash)
 		const uint8_t *ptr = data;
 		while (len > 0) {
 			int xfer_len = (len > 512)?512:len;
-			int tx_end;
+			Jtag::tapState_t tx_end;
 			if (len - xfer_len == 0)
 				tx_end = Jtag::RUN_TEST_IDLE;
 			else
diff --git a/src/efinix.cpp b/src/efinix.cpp
index 63cfbc0..267eeb8 100644
--- a/src/efinix.cpp
+++ b/src/efinix.cpp
@@ -291,7 +291,8 @@ void Efinix::programSPI(unsigned int offset, const uint8_t *data,
 
 void Efinix::programJTAG(const uint8_t *data, const int length)
 {
-	int xfer_len = 512, tx_end;
+	int xfer_len = 512;
+	Jtag::tapState_t tx_end;
 	uint8_t tx[512];
 
 	if (_fpga_family == TITANIUM_FAMILY)
diff --git a/src/gowin.cpp b/src/gowin.cpp
index 1706d15..7568927 100644
--- a/src/gowin.cpp
+++ b/src/gowin.cpp
@@ -632,7 +632,8 @@ bool Gowin::connectJtagToMCU()
 /* TN653 p. 9 */
 bool Gowin::flashSRAM(const uint8_t *data, int length)
 {
-	int tx_len, tx_end;
+	int tx_len;
+	Jtag::tapState_t tx_end;
 	int byte_length = length / 8;
 
 	ProgressBar progress("Flash SRAM", byte_length, 50, _quiet);
diff --git a/src/jtag.cpp b/src/jtag.cpp
index 1bd8d7d..65c9145 100644
--- a/src/jtag.cpp
+++ b/src/jtag.cpp
@@ -317,7 +317,7 @@ void Jtag::toggleClk(int nb)
 	return;
 }
 
-int Jtag::shiftDR(const uint8_t *tdi, unsigned char *tdo, int drlen, int end_state)
+int Jtag::shiftDR(const uint8_t *tdi, unsigned char *tdo, int drlen, tapState_t end_state)
 {
 	/* get number of devices in the JTAG chain
 	 * after the selected one
@@ -370,7 +370,7 @@ int Jtag::shiftDR(const uint8_t *tdi, unsigned char *tdo, int drlen, int end_sta
 	return 0;
 }
 
-int Jtag::shiftIR(unsigned char tdi, int irlen, int end_state)
+int Jtag::shiftIR(unsigned char tdi, int irlen, tapState_t end_state)
 {
 	if (irlen > 8) {
 		cerr << "Error: this method this direct char don't support more than 1 byte" << endl;
@@ -379,7 +379,7 @@ int Jtag::shiftIR(unsigned char tdi, int irlen, int end_state)
 	return shiftIR(&tdi, NULL, irlen, end_state);
 }
 
-int Jtag::shiftIR(unsigned char *tdi, unsigned char *tdo, int irlen, int end_state)
+int Jtag::shiftIR(unsigned char *tdi, unsigned char *tdo, int irlen, tapState_t end_state)
 {
 	display("%s: avant shiftIR\n", __func__);
 	int bypass_after = 0;
diff --git a/src/jtag.hpp b/src/jtag.hpp
index aaddedd..91190ce 100644
--- a/src/jtag.hpp
+++ b/src/jtag.hpp
@@ -67,22 +67,6 @@ class Jtag {
 	 * \return a pointer instance of JtagInterface
 	 */
 	JtagInterface *get_ll_class() {return _jtag;}
-
-	int shiftIR(unsigned char *tdi, unsigned char *tdo, int irlen,
-		int end_state = RUN_TEST_IDLE);
-	int shiftIR(unsigned char tdi, int irlen,
-		int end_state = RUN_TEST_IDLE);
-	int shiftDR(const uint8_t *tdi, unsigned char *tdo, int drlen,
-		int end_state = RUN_TEST_IDLE);
-	int read_write(const uint8_t *tdi, unsigned char *tdo, int len, char last);
-
-	void toggleClk(int nb);
-	void go_test_logic_reset();
-	void set_state(int newState);
-	int flushTMS(bool flush_buffer = false);
-	void flush() {flushTMS(); _jtag->flush();}
-	void setTMS(unsigned char tms);
-
 	enum tapState_t {
 		TEST_LOGIC_RESET = 0,
 		RUN_TEST_IDLE = 1,
@@ -102,6 +86,22 @@ class Jtag {
 		UPDATE_IR = 15,
 		UNKNOWN = 999
 	};
+
+	int shiftIR(unsigned char *tdi, unsigned char *tdo, int irlen,
+				Jtag::tapState_t end_state = RUN_TEST_IDLE);
+	int shiftIR(unsigned char tdi, int irlen,
+		Jtag::tapState_t end_state = RUN_TEST_IDLE);
+	int shiftDR(const uint8_t *tdi, unsigned char *tdo, int drlen,
+		Jtag::tapState_t end_state = RUN_TEST_IDLE);
+	int read_write(const uint8_t *tdi, unsigned char *tdo, int len, char last);
+
+	void toggleClk(int nb);
+	void go_test_logic_reset();
+	void set_state(int newState);
+	int flushTMS(bool flush_buffer = false);
+	void flush() {flushTMS(); _jtag->flush();}
+	void setTMS(unsigned char tms);
+
 	const char *getStateName(tapState_t s);
 
 	/* utilities */
diff --git a/src/lattice.cpp b/src/lattice.cpp
index 8ddf7b5..01ea945 100644
--- a/src/lattice.cpp
+++ b/src/lattice.cpp
@@ -338,7 +338,7 @@ bool Lattice::program_mem()
 
 	uint8_t tmp[1024];
 	int size = 1024;
-	int next_state = Jtag::SHIFT_DR;
+	Jtag::tapState_t next_state = Jtag::SHIFT_DR;
 
 	ProgressBar progress("Loading", length, 50, _quiet);
 
@@ -433,7 +433,7 @@ bool Lattice::program_intFlash(ConfigBitstreamParser *_cbp)
 
 				if(ufm_start > 2045) {
 					printError("UFM section detected in JEDEC file, but "
-					 	"calculated flash start address was out of bounds");
+						"calculated flash start address was out of bounds");
 					return false;
 				}
 			} else if (note == "END CONFIG DATA") {
@@ -1308,7 +1308,7 @@ uint16_t Lattice::getUFMStartPageFromJEDEC(JedParser *_jed, int id)
 	addres.
 	TODO: In any case, JEDEC files don't carry part information. Verify against
 	IDCODE read previously? */
-	
+
 	if(raw_page_offset > 9211) {
 		return raw_page_offset - 9211 - 1; // 7000
 	} else if(raw_page_offset > 5758) {
diff --git a/src/svf_jtag.cpp b/src/svf_jtag.cpp
index a5334cf..a971b75 100644
--- a/src/svf_jtag.cpp
+++ b/src/svf_jtag.cpp
@@ -245,13 +245,13 @@ void SVF_jtag::handle_instruction(vector<string> const &vstr)
 		if (_verbose) cout << "trst value : " << vstr[1] << endl;
 	} else if (!vstr[0].compare("ENDDR")) {
 		if (_verbose) cout << "enddr value : " << vstr[1] << endl;
-		_enddr = fsm_state[vstr[1]];
+		_enddr = (Jtag::tapState_t)fsm_state[vstr[1]];
 	} else if (!vstr[0].compare("ENDIR")) {
 		if (_verbose) cout << "endir value : " << vstr[1] << endl;
-		_endir = fsm_state[vstr[1]];
+		_endir = (Jtag::tapState_t)fsm_state[vstr[1]];
 	} else if (!vstr[0].compare("STATE")) {
 		if (_verbose) cout << "state value : " << vstr[1] << endl;
-		_jtag->set_state(fsm_state[vstr[1]]);
+		_jtag->set_state((Jtag::tapState_t)fsm_state[vstr[1]]);
 	} else if (!vstr[0].compare("RUNTEST")) {
 		parse_runtest(vstr);
 	} else if (!vstr[0].compare("HIR")) {
@@ -284,7 +284,7 @@ void SVF_jtag::handle_instruction(vector<string> const &vstr)
 		parse_XYR(vstr, sir);
 		if (_verbose) {
 			for (auto &&t : vstr)
-			 	cout << t << " ";
+				cout << t << " ";
 			cout << endl;
 			cout << "\tlen   : " << sir.len << endl;
 			cout << "\ttdo   : " << sir.tdo.size()*4 << endl;
@@ -335,7 +335,7 @@ void SVF_jtag::handle_instruction(vector<string> const &vstr)
 }
 
 SVF_jtag::SVF_jtag(Jtag *jtag, bool verbose):_verbose(verbose), _freq_hz(0),
-	_enddr(fsm_state["IDLE"]), _endir(fsm_state["IDLE"]),
+	_enddr((Jtag::tapState_t)fsm_state["IDLE"]), _endir((Jtag::tapState_t)fsm_state["IDLE"]),
 	_run_state(fsm_state["IDLE"]), _end_state(fsm_state["IDLE"])
 
 {
diff --git a/src/svf_jtag.hpp b/src/svf_jtag.hpp
index d5d916e..b5164ab 100644
--- a/src/svf_jtag.hpp
+++ b/src/svf_jtag.hpp
@@ -58,8 +58,8 @@ class SVF_jtag {
 	bool _verbose;
 
 	uint32_t _freq_hz;
-	int _enddr;
-	int _endir;
+	Jtag::tapState_t _enddr;
+	Jtag::tapState_t _endir;
 	int _run_state;
 	int _end_state;
 	svf_XYR hdr;
diff --git a/src/xilinx.cpp b/src/xilinx.cpp
index 7d2c473..e2ac32a 100644
--- a/src/xilinx.cpp
+++ b/src/xilinx.cpp
@@ -571,7 +571,8 @@ void Xilinx::program_mem(ConfigBitstreamParser *bitfile)
 	/* GGM: TODO */
 	int byte_length = bitfile->getLength() / 8;
 	const uint8_t *data = bitfile->getData();
-	int tx_len, tx_end;
+	int tx_len;
+	Jtag::tapState_t tx_end;
 	int burst_len = byte_length / 100;
 
 	ProgressBar progress("Flash SRAM", byte_length, 50, _quiet);
@@ -728,7 +729,8 @@ bool Xilinx::xc3s_flow_program(ConfigBitstreamParser *bit)
 	int byte_length = bit->getLength() / 8;
 	int burst_len = byte_length / 100;
 	const uint8_t *data = bit->getData();
-	int tx_len = burst_len * 8, tx_end = Jtag::SHIFT_DR;
+	int tx_len = burst_len * 8;
+	Jtag::tapState_t tx_end = Jtag::SHIFT_DR;
 	ProgressBar progress("Flash SRAM", byte_length, 50, _quiet);
 
 	flow_enable();
@@ -1081,7 +1083,7 @@ bool Xilinx::xcf_program(ConfigBitstreamParser *bitfile)
 	uint32_t data_len = bitfile->getLength() / 8;
 	uint32_t xfer_len, offset = 0;
 	uint32_t addr = 0;
-	int xfer_end;
+	Jtag::tapState_t xfer_end;
 
 	/* limit JTAG clock frequency to 15MHz */
 	if (_jtag->getClkFreq() > 15e6)