diff --git a/cmd_parser.c b/cmd_parser.c
index 421b860..c56105e 100644
--- a/cmd_parser.c
+++ b/cmd_parser.c
@@ -70,6 +70,8 @@ __xdata signed char cmd_words_b[N_WORDS];
 __xdata uint8_t cmd_history[CMD_HISTORY_SIZE];
 __xdata uint16_t cmd_history_ptr;
 
+// Error set by commands
+__xdata uint8_t err_status;
 
 inline uint8_t isletter(uint8_t l)
 {
@@ -1172,6 +1174,7 @@ uint8_t cmd_tokenize(void) __banked
 	print_string_x(&cmd_buffer[0]);
 	write_char('<'); write_char('\n');
 #endif
+	err_status = ERR_OK;
 	line_ptr = 0;
 	is_white = 1;
 	uint8_t word = 0;
@@ -1189,11 +1192,14 @@ uint8_t cmd_tokenize(void) __banked
 		line_ptr++;
 		if (word >= N_WORDS - 1) {
 			print_string("\ntoo many arguments, truncated");
+			err_status = ERR_TOO_MANY_ARGUMENTS;
 			return 1;
 		}
 	}
-	if (line_ptr == CMD_BUF_SIZE - 1)
+	if (line_ptr == CMD_BUF_SIZE - 1) {
+		err_status = ERR_CMD_TOO_LONG;
 		return 1;
+	}
 	cmd_words_b[word++] = line_ptr;
 	cmd_words_b[word++] = -1;
 
@@ -1481,15 +1487,20 @@ void clear_command_history(void) __banked
 
 #define FLASH_READ_BURST_SIZE 0x100
 #define PASSWORD "1234"
+
+#if CONFIG_LEN % FLASH_READ_BURST_SIZE
+	#error "CONFIG_LEN not a multiple of FLASH_READ_BURST_SIZE"
+#endif
 void execute_config(void) __banked
 {
 	__xdata uint32_t pos = CONFIG_START;
-	__xdata uint16_t len_left = CONFIG_LEN;
+	__xdata uint8_t pages_left = CONFIG_LEN / FLASH_READ_BURST_SIZE;
 
 	// Set default password, it can be overwritten in the configuration file
 	strtox(passwd, PASSWORD);
 	save_cmd = 0;
 
+	uint8_t cmd_idx = 0;
 	do {
 		flash_region.addr = pos;
 		flash_region.len = FLASH_READ_BURST_SIZE;
@@ -1498,24 +1509,35 @@ void execute_config(void) __banked
 		__xdata uint8_t cfg_idx = 0;
 		uint8_t c = 0;
 		do {
-			for (uint8_t cmd_idx = 0; cmd_idx < (CMD_BUF_SIZE - 1); cmd_idx++) {
-				c = flash_buf[cfg_idx++];
-				if (c == 0 || c == '\n') {
-					cmd_buffer[cmd_idx] = '\0';
-					if (cmd_idx && !cmd_tokenize())
-						cmd_parser();
-					if (c == 0)
+			if (cmd_idx >= (CMD_BUF_SIZE - 1)) {
+				cmd_buffer[cmd_idx] = '\0';
+				print_string("ERROR: Command too long: ");
+				print_string_x(cmd_buffer);
+				write_char('\n');
+				err_status = ERR_CMD_TOO_LONG;
+				goto config_done;
+			}
+			c = flash_buf[cfg_idx++];
+			if (c == 0 || c == '\n') {
+				cmd_buffer[cmd_idx] = '\0';
+				if (cmd_idx && !cmd_tokenize()) {
+					cmd_parser();
+					if (err_status)
 						goto config_done;
-					break;
 				}
-
-				cmd_buffer[cmd_idx] = c;
+				if (c == 0)
+					goto config_done;
+				cmd_idx = 0;
+				continue;
 			}
-		} while(cfg_idx);
 
-		len_left -= FLASH_READ_BURST_SIZE;
+			cmd_buffer[cmd_idx] = c;
+			cmd_idx++;
+		} while (cfg_idx);
+
+		pages_left--;
 		pos += FLASH_READ_BURST_SIZE;
-	} while(len_left);
+	} while(pages_left);
 
 config_done:
 	// Start saving commands to cmd_history
diff --git a/rtl837x_common.h b/rtl837x_common.h
index 293c755..7933687 100644
--- a/rtl837x_common.h
+++ b/rtl837x_common.h
@@ -45,6 +45,11 @@ extern __xdata uint8_t sbuf[SBUF_SIZE];
 // Size of the flash buffer used for writing to flash, must be a multiple of the flash page size (0x100)
 #define FLASH_BUF_SIZE 512
 
+// Errors for commands
+#define ERR_OK			0
+#define ERR_TOO_MANY_ARGUMENTS	1
+#define ERR_CMD_TOO_LONG	2
+
 // For RX data, a propriatary RTL FRAME is inserted. Instead of 0x0800 for IPv4,
 // the RTL_FRAME_TAG_ID is used as part of an 8-byte tag. When VLAN is activated,
 // the VLAN tag is inserted after the RTL tag