diff --git a/21_m1284p_WIZNET_TFTP_client_FATFS/Internet/TFTP/tftp.c b/21_m1284p_WIZNET_TFTP_client_FATFS/Internet/TFTP/tftp.c
index 4ab80c6..c2cc823 100644
--- a/21_m1284p_WIZNET_TFTP_client_FATFS/Internet/TFTP/tftp.c
+++ b/21_m1284p_WIZNET_TFTP_client_FATFS/Internet/TFTP/tftp.c
@@ -26,23 +26,18 @@ void save_data(uint8_t *data, uint32_t data_len, uint16_t block_number)
 	//Nothing to do with received data yet..
 	//TODO: Add your own handler here
 	//Print out data as string
-	/*
-	uint8_t _tmp_msg[256] = "\0";
-	memset(_tmp_msg, 0x0, 256);
-	strncpy(_tmp_msg, data, data_len);
-	*/
 	uint8_t * str;
 	str = data;
 	str += data_len;
 	*str = 0x0;
-	PRINTF("++Data #%d-%lu:\r\n%s\r\n", block_number, data_len, data);
+	PRINTF("\r\n++Data #%d-%lu:\r\n%s\r\n", block_number, data_len, data);
 }
 #endif
 
 /* Global Variable ----------------------------------------------*/
 static int		g_tftp_socket = -1;
 
-static uint8_t g_filename[FILE_NAME_SIZE];
+static uint8_t g_filename[TFTP_FILE_NAME_SIZE];
 
 static uint32_t g_server_ip = 0;
 static uint16_t g_server_port = 0;
@@ -66,7 +61,7 @@ static TFTP_OPTION default_tftp_opt = {
 uint8_t g_progress_state = TFTP_PROGRESS;
 
 #ifdef __TFTP_DEBUG__
-int dbg_level = (INFO_DBG | ERROR_DBG | IPC_DBG);
+int dbg_level = (INFO_DBG | ERROR_DBG | IPC_DBG | DEBUG_DBG);
 #endif
 
 /* static function define ---------------------------------------*/
@@ -145,9 +140,9 @@ static int open_tftp_socket(uint8_t sock)
 {
 	uint8_t sd, sck_state;
 
-	sd = socket(sock, Sn_MR_UDP, 51000, SF_IO_NONBLOCK);
+	sd = socket(sock, Sn_MR_UDP, TFTP_LOCAL_PORT, SF_IO_NONBLOCK);
 	if(sd != sock) {
-		//DBG_PRINT(ERROR_DBG, "[%s] socket error\r\n", __func__);
+		DBG_PRINT(ERROR_DBG, "[%s] socket error\r\n", __func__);
 		return -1;
 	}
 
@@ -155,7 +150,7 @@ static int open_tftp_socket(uint8_t sock)
 		getsockopt(sd , SO_STATUS, &sck_state);
 	} while(sck_state != SOCK_UDP);
 
-	return sd;
+	return (int)sd;
 }
 
 static int send_udp_packet(int socket, uint8_t *packet, uint32_t len, uint32_t ip, uint16_t port)
@@ -593,8 +588,21 @@ void TFTP_init(uint8_t socket, uint8_t *buf)
 {
 	init_tftp();
 
-	g_tftp_socket = open_tftp_socket(socket);
 	g_tftp_rcv_buf = buf;
+	g_tftp_socket = open_tftp_socket(socket);
+	if(g_tftp_socket == -1)
+	{
+		//Here when TFTP socket open OK
+		DBG_PRINT(ERROR_DBG, "--[%s] TFTP socket[%d] open error\r\nReboot the board..\r\n", __func__, socket);
+		while(1)
+		{
+			;
+		}
+	}
+	else
+	{
+		DBG_PRINT(INFO_DBG, "++[%s] TFTP socket[%d]:%u open success\r\n", __func__, g_tftp_socket, TFTP_LOCAL_PORT);
+	}
 }
 
 void TFTP_exit(void)
@@ -663,7 +671,7 @@ void TFTP_read_request(uint32_t server_ip, uint8_t *filename)
 {
 	set_server_ip(server_ip);
 #ifdef __TFTP_DEBUG__
-	DBG_PRINT(INFO_DBG, "[%s] Set Tftp Server : 0x%lx\r\n", __func__, server_ip);
+	DBG_PRINT(INFO_DBG, "[%s] Set Tftp Server : 0x%lX\r\n", __func__, server_ip);
 #endif
 
 	g_progress_state = TFTP_PROGRESS;
diff --git a/21_m1284p_WIZNET_TFTP_client_FATFS/Internet/TFTP/tftp.h b/21_m1284p_WIZNET_TFTP_client_FATFS/Internet/TFTP/tftp.h
index 61644d7..49f64b7 100644
--- a/21_m1284p_WIZNET_TFTP_client_FATFS/Internet/TFTP/tftp.h
+++ b/21_m1284p_WIZNET_TFTP_client_FATFS/Internet/TFTP/tftp.h
@@ -36,7 +36,7 @@ FRESULT fr;	// FatFs function common result code
 
 #define DBG_PRINT(level, format, args...)		{ \
 											if(dbg_level & level) \
-												printf(format, ##args); \
+												PRINTF(format, ##args); \
 										}
 
 #define NORMAL_MODE		0
@@ -71,10 +71,10 @@ extern int dbg_level;
 
 /* define */
 #define TFTP_SERVER_PORT		69
-#define TFTP_TEMP_PORT			51000
+#define TFTP_LOCAL_PORT			51000
 #define TFTP_BLK_SIZE			512
 #define MAX_MTU_SIZE			1514
-#define FILE_NAME_SIZE			20
+#define TFTP_FILE_NAME_SIZE			20
 
 //#define __TFTP_DEBUG__
 
diff --git a/21_m1284p_WIZNET_TFTP_client_FATFS/main.c b/21_m1284p_WIZNET_TFTP_client_FATFS/main.c
index 1d8189c..2bcc3e4 100644
--- a/21_m1284p_WIZNET_TFTP_client_FATFS/main.c
+++ b/21_m1284p_WIZNET_TFTP_client_FATFS/main.c
@@ -218,7 +218,7 @@ uint16_t adc_read(uint8_t channel)
 //***************** TFTP client INIT: BEGIN
 uint8_t g_tftp_socket_rcv_buf[MAX_MTU_SIZE];
 uint8_t g_tftp_op_mode = NORMAL_MODE;
-uint8_t tftp_filename[50];
+uint8_t tftp_filename[TFTP_FILE_NAME_SIZE];
 uint32_t tftp_server;
 //***************** TFTP client INIT: END
 
@@ -564,11 +564,10 @@ int main()
 
 
 					printf("\r\n########## SW1 was pressed.\r\n");
-					//strncpy(tftp_filename, 0x00, 50);
-					memset(tftp_filename, 0x0, 50);
-					//strncpy(tftp_filename, "test.txt", 8);
-					//strncpy(tftp_filename, "README.md", 9);
-					strncpy(tftp_filename, "tftpd32.ini", 11);
+					memset(tftp_filename, 0x0, 20);
+					//strncpy(tftp_filename, "test.txt", TFTP_FILE_NAME_SIZE);
+					strncpy(tftp_filename, "README.md", TFTP_FILE_NAME_SIZE);
+					//strncpy(tftp_filename, "tftpd32.ini", TFTP_FILE_NAME_SIZE);
 
 					tftp_server = ((uint32_t)tftp_destip[0] << 24) | ((uint32_t)tftp_destip[1] << 16) | ((uint32_t)tftp_destip[2] << 8) | ((uint32_t)tftp_destip[3]);
 
@@ -587,12 +586,11 @@ int main()
 						_ret = TFTP_run();
 						if(_ret != TFTP_PROGRESS)
 							break;
-						_delay_ms(1);//Just for debug
+						//_delay_ms(1);//Just for debug
 					}
-					_delay_ms(1000);//Just for debug
+					_delay_ms(1000);
 
 					//!! Debug only
-					//PRINTF("SW1 is pressed\r\nADC0/PA0 is: %u\r\n", adc_read(0));
 					//PRINTF("SW1 is pressed\r\n");