diff --git a/src/device.hpp b/src/device.hpp
index 7295772..c913402 100644
--- a/src/device.hpp
+++ b/src/device.hpp
@@ -52,6 +52,8 @@ class Device {
 		virtual int  idCode() = 0;
 		virtual void reset();
 
+		virtual bool connectJtagToMCU() {return false;}
+
 	protected:
 		Jtag *_jtag;
 		std::string _filename;
diff --git a/src/gowin.cpp b/src/gowin.cpp
index 604ff7d..1637146 100644
--- a/src/gowin.cpp
+++ b/src/gowin.cpp
@@ -58,6 +58,7 @@ using namespace std;
 #  define STATUS_FLASH_LOCK			(1 << 17)
 #define EF_PROGRAM			0x71
 #define EFLASH_ERASE		0x75
+#define SWITCH_TO_MCU_JTAG		0x7a
 
 /* BSCAN spi (external flash) (see below for details) */
 /* most common pins def */
@@ -73,7 +74,7 @@ using namespace std;
 #define BSCAN_GW1NSR_4C_SPI_DO  (1 << 1)
 #define BSCAN_GW1NSR_4C_SPI_MSK ((0x01 << 0))
 
-Gowin::Gowin(Jtag *jtag, const string filename, const string &file_type,
+Gowin::Gowin(Jtag *jtag, const string filename, const string &file_type, std::string mcufw,
 		Device::prog_type_t prg_type, bool external_flash,
 		bool verify, int8_t verbose): Device(jtag, filename, file_type,
 		verify, verbose), is_gw1n1(false), _external_flash(external_flash),
@@ -82,7 +83,9 @@ Gowin::Gowin(Jtag *jtag, const string filename, const string &file_type,
 		_spi_msk(BSCAN_SPI_MSK)
 {
 	_fs = NULL;
-	uint32_t idcode = _jtag->get_target_device_id();;
+	_mcufw = NULL;
+
+	uint32_t idcode = _jtag->get_target_device_id();
 
 	if (prg_type == Device::WR_FLASH)
 		_mode = Device::FLASH_MODE;
@@ -153,12 +156,29 @@ Gowin::Gowin(Jtag *jtag, const string filename, const string &file_type,
 			/* FIXME: implement GW2 checksum calculation */
 			skip_checksum = true;
 	};
+
+	if (mcufw.size() > 0) {
+		if (idcode != 0x0100981b)
+			throw std::runtime_error("Microcontroller firmware flashing only supported on GW1NSR-4C");
+		
+		_mcufw = new RawParser(mcufw, false);
+
+		if (_mcufw->parse() == EXIT_FAILURE) {
+			printError("FAIL");
+			delete _mcufw;
+			throw std::runtime_error("can't parse file");
+		} else {
+			printSuccess("DONE");
+		}
+	}
 }
 
 Gowin::~Gowin()
 {
 	if (_fs)
 		delete _fs;
+	if (_mcufw)
+		delete _mcufw;
 }
 
 void Gowin::reset()
@@ -170,11 +190,17 @@ void Gowin::reset()
 void Gowin::programFlash()
 {
 	int status;
-	uint8_t *data;
-	int length;
 
-	data = _fs->getData();
-	length = _fs->getLength();
+	uint8_t *data = _fs->getData();
+	int length = _fs->getLength();
+	
+	uint8_t *mcu_data = nullptr;
+	int mcu_length = 0;
+	
+	if (_mcufw) {
+		mcu_data = _mcufw->getData();
+		mcu_length = _mcufw->getLength();
+	}
 
 	/* erase SRAM */
 	if (!EnableCfg())
@@ -192,8 +218,12 @@ void Gowin::programFlash()
 	if (!DisableCfg())
 		return;
 	/* test status a faire */
-	if (!flashFLASH(data, length))
+	if (!flashFLASH(0, data, length))
 		return;
+	if (mcu_data) {
+		if (!flashFLASH(0x380, mcu_data, mcu_length))
+			return;
+	}
 	if (_verify)
 		printWarn("writing verification not supported");
 	if (!DisableCfg())
@@ -222,8 +252,6 @@ void Gowin::programFlash()
 
 void Gowin::program(unsigned int offset, bool unprotect_flash)
 {
-	(void) offset;
-
 	uint8_t *data;
 	uint32_t status;
 	int length;
@@ -435,55 +463,69 @@ bool Gowin::pollFlag(uint32_t mask, uint32_t value)
 }
 
 /* TN653 p. 17-21 */
-bool Gowin::flashFLASH(uint8_t *data, int length)
+bool Gowin::flashFLASH(uint32_t page, uint8_t *data, int length)
 {
 	uint8_t tx[4] = {0x4E, 0x31, 0x57, 0x47};
 	uint8_t tmp[4];
 	uint32_t addr;
 	int nb_iter;
 	int byte_length = length / 8;
+	int buffer_length;
+	uint8_t *buffer;
+	int nb_xpage;
 	uint8_t tt[39];
 	memset(tt, 0, 39);
 
 	_jtag->go_test_logic_reset();
 
-	/* we have to send
-	 * bootcode a X=0, Y=0 (4Bytes)
-	 * 5 x 32 dummy bits
-	 * full bitstream
-	 */
-	int buffer_length = byte_length+(6*4);
-	unsigned char bufvalues[]={
-									0x47, 0x57, 0x31, 0x4E,
-									0xff, 0xff , 0xff, 0xff,
-									0xff, 0xff , 0xff, 0xff,
-									0xff, 0xff , 0xff, 0xff,
-									0xff, 0xff , 0xff, 0xff,
-									0xff, 0xff , 0xff, 0xff};
+	if (page == 0) {
+		/* we have to send
+		 * bootcode a X=0, Y=0 (4Bytes)
+		 * 5 x 32 dummy bits
+		 * full bitstream
+		 */
+		buffer_length = byte_length+(6*4);
+		unsigned char bufvalues[]={
+										0x47, 0x57, 0x31, 0x4E,
+										0xff, 0xff , 0xff, 0xff,
+										0xff, 0xff , 0xff, 0xff,
+										0xff, 0xff , 0xff, 0xff,
+										0xff, 0xff , 0xff, 0xff,
+										0xff, 0xff , 0xff, 0xff};
+		nb_xpage = buffer_length/256;
+		if (nb_xpage * 256 != buffer_length) {
+			nb_xpage++;
+			buffer_length = nb_xpage * 256;
+		}
 
-	int nb_xpage = buffer_length/256;
-	if (nb_xpage * 256 != buffer_length) {
-		nb_xpage++;
-		buffer_length = nb_xpage * 256;
+		buffer = new uint8_t[buffer_length];
+		/* fill theorical size with 0xff */
+		memset(buffer, 0xff, buffer_length);
+		/* fill first page with code */
+		memcpy(buffer, bufvalues, 6*4);
+		/* bitstream just after opcode */
+		memcpy(buffer+6*4, data, byte_length);
+	} else {
+		buffer_length = byte_length;
+		nb_xpage = buffer_length/256;
+		if (nb_xpage * 256 != buffer_length) {
+			nb_xpage++;
+			buffer_length = nb_xpage * 256;
+		}
+		buffer = new uint8_t[buffer_length];
+		memset(buffer, 0xff, buffer_length);
+		memcpy(buffer, data, byte_length);
 	}
 
-	unsigned char buffer[buffer_length];
-	/* fill theorical size with 0xff */
-	memset(buffer, 0xff, buffer_length);
-	/* fill first page with code */
-	memcpy(buffer, bufvalues, 6*4);
-	/* bitstream just after opcode */
-	memcpy(buffer+6*4, data, byte_length);
-
 
 	ProgressBar progress("write Flash", buffer_length, 50, _quiet);
 
-	for (int i=0, xpage=0; xpage < nb_xpage; i+=(nb_iter*4), xpage++) {
+	for (int i=0, xpage = 0; xpage < nb_xpage; i += (nb_iter * 4), xpage++) {
 		wr_rd(CONFIG_ENABLE, NULL, 0, NULL, 0);
 		wr_rd(EF_PROGRAM, NULL, 0, NULL, 0);
-		if (xpage != 0)
+		if ((page + xpage) != 0)
 			_jtag->toggleClk(312);
-		addr = xpage << 6;
+		addr = (page + xpage) << 6;
 		tmp[3] = 0xff&(addr >> 24);
 		tmp[2] = 0xff&(addr >> 16);
 		tmp[1] = 0xff&(addr >> 8);
@@ -499,8 +541,12 @@ bool Gowin::flashFLASH(uint8_t *data, int length)
 
 		for (int ypage = 0; ypage < nb_iter; ypage++) {
 			unsigned char *t = buffer+xoffset + 4*ypage;
-			for (int x=0; x < 4; x++)
-				tx[3-x] = t[x];
+			for (int x=0; x < 4; x++) {
+				if (page == 0)
+					tx[3-x] = t[x];
+				else
+					tx[x] = t[x];
+			}
 			_jtag->shiftDR(tx, NULL, 32);
 
 			if (!is_gw1n1)
@@ -518,6 +564,13 @@ bool Gowin::flashFLASH(uint8_t *data, int length)
 	_jtag->set_state(Jtag::RUN_TEST_IDLE);
 
 	progress.done();
+	delete[] buffer;
+	return true;
+}
+
+bool Gowin::connectJtagToMCU()
+{
+	wr_rd(SWITCH_TO_MCU_JTAG, NULL, 0, NULL, 0);
 	return true;
 }
 
diff --git a/src/gowin.hpp b/src/gowin.hpp
index d26889e..c628505 100644
--- a/src/gowin.hpp
+++ b/src/gowin.hpp
@@ -18,7 +18,7 @@
 
 class Gowin: public Device, SPIInterface {
 	public:
-		Gowin(Jtag *jtag, std::string filename, const std::string &file_type,
+		Gowin(Jtag *jtag, std::string filename, const std::string &file_type, std::string mcufw,
 				Device::prog_type_t prg_type, bool external_flash,
 				bool verify, int8_t verbose);
 		~Gowin();
@@ -26,6 +26,7 @@ class Gowin: public Device, SPIInterface {
 		void reset() override;
 		void program(unsigned int offset, bool unprotect_flash) override;
 		void programFlash();
+		bool connectJtagToMCU() override;
 
 		/* spi interface */
 		virtual bool protect_flash(uint32_t len) override {
@@ -48,7 +49,7 @@ class Gowin: public Device, SPIInterface {
 		bool eraseSRAM();
 		bool eraseFLASH();
 		bool flashSRAM(uint8_t *data, int length);
-		bool flashFLASH(uint8_t *data, int length);
+		bool flashFLASH(uint32_t page, uint8_t *data, int length);
 		void displayReadReg(uint32_t dev);
 		uint32_t readStatusReg();
 		uint32_t readUserCode();
@@ -61,5 +62,6 @@ class Gowin: public Device, SPIInterface {
 		uint8_t _spi_di;      /**< di signal (mosi) offset in bscan SPI */
 		uint8_t _spi_do;      /**< do signal (miso) offset in bscan SPI */
 		uint8_t _spi_msk;     /** default spi msk with only do out */
+		ConfigBitstreamParser *_mcufw;
 };
 #endif  // GOWIN_HPP_
diff --git a/src/main.cpp b/src/main.cpp
index 29e070a..6ed5699 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -78,6 +78,8 @@ struct arguments {
 	bool xvc;
 	int port;
 	string interface;
+	string mcufw;
+	bool conmcu;
 };
 
 int run_xvc_server(const struct arguments &args, const cable_t &cable,
@@ -506,7 +508,7 @@ int main(int argc, char **argv)
 			fpga = new Efinix(jtag, args.bit_file, args.file_type,
 				/*DBUS4 | DBUS7, DBUS5*/args.board, args.verify, args.verbose);
 		} else if (fab == "Gowin") {
-			fpga = new Gowin(jtag, args.bit_file, args.file_type,
+			fpga = new Gowin(jtag, args.bit_file, args.file_type, args.mcufw,
 				args.prg_type, args.external_flash, args.verify, args.verbose);
 		} else if (fab == "lattice") {
 			fpga = new Lattice(jtag, args.bit_file, args.file_type,
@@ -537,6 +539,10 @@ int main(int argc, char **argv)
 		}
 	}
 
+	if (args.conmcu == true) {
+		fpga->connectJtagToMCU();
+	}
+
 	/* unprotect SPI flash */
 	if (args.unprotect_flash && args.bit_file.empty()) {
 		fpga->unprotect_flash();
@@ -721,6 +727,10 @@ int parse_opt(int argc, char **argv, struct arguments *args, jtag_pins_conf_t *p
 #endif
 			("port", "Xilinx Virtual Cable Port (default 3721)",
 				cxxopts::value<int>(args->port))
+			("mcufw", "Microcontroller firmware",
+				cxxopts::value<std::string>(args->mcufw))
+			("conmcu", "Connect JTAG to MCU",
+				cxxopts::value<bool>(args->conmcu))
 			("V,Version", "Print program version");
 
 		options.parse_positional({"bitstream"});
@@ -845,7 +855,8 @@ int parse_opt(int argc, char **argv, struct arguments *args, jtag_pins_conf_t *p
 			!args->protect_flash &&
 			!args->unprotect_flash &&
 			!args->xvc &&
-			!args->reset) {
+			!args->reset &&
+			!args->conmcu) {
 			printError("Error: bitfile not specified");
 			cout << options.help() << endl;
 			throw std::exception();