diff --git a/usbboot/src/cmd.c b/usbboot/src/cmd.c
index f931196..410d831 100644
--- a/usbboot/src/cmd.c
+++ b/usbboot/src/cmd.c
@@ -568,7 +568,7 @@ int nand_prog(void)
 		" \t-e:\twith oob and ecc\n";
 
 	if (com_argc != 6) {
-		printf(" not enough argument.\n");
+		printf(" arguments count error.\n");
 		printf("%s", help);
 		return 0;
 	}
@@ -578,6 +578,7 @@ int nand_prog(void)
 	nand_in.start = atoi(com_argv[1]);
 	image_file = com_argv[2];
 	nand_in.dev = atoi(com_argv[3]);
+
 	(nand_in.cs_map)[atoi(com_argv[4])] = 1;
 	if (!strcmp(com_argv[5], "-e")) 
 		nand_in.option = OOB_ECC;
diff --git a/usbboot/src/command_line.c b/usbboot/src/command_line.c
index b2cbb36..7d0d997 100644
--- a/usbboot/src/command_line.c
+++ b/usbboot/src/command_line.c
@@ -223,39 +223,22 @@ int handle_load(void)
 
 int command_interpret(char * com_buf)
 {
-	char *buf = com_buf;
-	int k, L, i = 0, j = 0;
-	
-	L = (int)strlen(buf);
-	buf[L]=' ';
-
-	if (buf[0] == '\n')
+	if(com_buf[0] == '\n')
 		return 0;
 
-	for (k = 0; k <= L; k++) {
-		if (*buf == ' ' || *buf == '\n') {
-			while ( *(++buf) == ' ' );
-			com_argv[i][j] = '\0';
-			i++;
-			if (i > MAX_ARGC)
-				return COMMAND_NUM + 1;
-			j = 0;
-			continue;
-		} else {
-			com_argv[i][j] = *buf;
-			j++;
-			if (j > MAX_COMMAND_LENGTH)
-				return COMMAND_NUM + 1;
-		}
-		buf++;
-	}
+	com_argc = 0;
+	char *p = strtok(com_buf, "\n ");
+	strcpy(com_argv[com_argc++], p);
 
-	com_argc = i;
+	while(p = strtok(NULL, "\n "))
+		strcpy(com_argv[com_argc++], p);
 
-	for (i = 1; i <= COMMAND_NUM; i++) 
-		if (!strcmp(COMMAND[i], com_argv[0])) 
-			return i;
-	return COMMAND_NUM + 1;
+	int loop = 0;
+	for (loop = 1; loop <= COMMAND_NUM; loop++)
+		if (!strcmp(COMMAND[loop], com_argv[0]))
+			return loop;
+
+	return -1;
 }
 
 int command_handle(char *buf)
@@ -317,6 +300,7 @@ int command_handle(char *buf)
 	case 29:
 		handle_memtest();
 		break;
+	case -1:
 	default:
 		printf(" command not support or input error!\n");
 		break;
diff --git a/usbboot/src/main.c b/usbboot/src/main.c
index 7d8807b..a2d7ead 100644
--- a/usbboot/src/main.c
+++ b/usbboot/src/main.c
@@ -1,6 +1,6 @@
 /*
  * Copyright(C) 2009  Qi Hardware Inc.,
- * Authors: Xiangfu Liu <xiangfu@qi-hardware.com>
+ * Authors: Xiangfu Liu <xiangfu@sharism.com>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -37,9 +37,10 @@ static void help(void)
 	       "  -h --help\t\t\tPrint this help message\n"
 	       "  -v --version\t\t\tPrint the version number\n"
 	       "  -c --command\t\t\tDirect run the commands, split by ';'\n"
-	       "  -f --configure\t\t\tconfigure file path\n"
+	       "              \t\t\tNOTICE: the max commands count is 10!\n"
+	       "  -f --configure\t\tconfigure file path\n"
 	       "  <run without options to enter commands via usbboot prompt>\n\n"
-	       "Report bugs to <xiangfu@qi-hardware.com>.\n"
+	       "Report bugs to <xiangfu@sharism.cc>.\n"
 		);
 }
 
@@ -107,17 +108,14 @@ int main(int argc, char **argv)
 		return EXIT_FAILURE;
 
 	if (command) {		/* direct run command */
-		char *delim=";";
-		char *p;
-		p = strtok(cmdpt, delim);
-		strcpy(com_buf, p);
-		printf(" Execute command: %s \n",com_buf);
-		command_handle(com_buf);
+		char *p[10];
+		int i, loop = 0;
+		p[loop++] = strtok(cmdpt, ";");
+		while(p[loop++] = strtok(NULL, ";"));
 
-		while((p = strtok(NULL,delim))) {
-			strcpy(com_buf, p);
-			printf(" Execute command: %s \n",com_buf);
-			command_handle(com_buf);
+		for(i = 0; i < loop - 1 && i < 10; i++) {
+			printf(" Execute command: %s \n",p[i]);
+			command_handle(p[i]);
 		}
 		goto out;
 	}