WIZ-DTU AT command

AT command will use different color to represent each kind of information.

Color	Meaning
Bold	Default value of the AT command
Blue	Parameters inputs for the AT command
Green	Return value of the AT command
Red	Special note of the AT command or Error message

Overview of AT Command

The AT command supported by WIZ-DTU serial to Ethernet converters is a standard interface that is not case sensitive and always starts with "AT" and ends with "\r\n". The format of its commands, return values, and parameters is fixed. Generally speaking, AT commands have the following formats:

1、No parameter command

Format: AT+\r\n

Explanation: The command is followed by no parameters or symbols.

Example:

Command: AT+EXIT\r\n

Response: OK\r\n

2、Query command

Format: AT＋"command"?\r\n

Description: Used to query the current configuration value of a parameter.

Example:

Command: AT+ECHO?\r\n

Response: [ECHO] Value is: 1\r\nOK\r\n

3、Command with parameters

Format: AT＋"command"="parameter"\r\n

Explanation: It is the most commonly used format for setting a certain parameter (except for the DEFAULT command and RESET).

Example:

Command: AT+ECHO=1\r\n

Response: [ECHO] Value is: 1\r\n OK\r\n

AT command Return values

According to the different AT commands input by the user, WIZ-DTU will reply with the execution results of the commands, as shown in the table below.

Response type	Response	Description
Error message	Command Invalid\r\nERROR\r\n	Command error
Error Info	Command parameter error or mismatch with current working mode
Correct information	OK\r\n	Parameter free command for correct configuration
[Command] Value is: value\r\nOK\r\n	Correct configuration of query commands and parameterized commands

Enter AT command mode

There are two operating modes for WIZ-DTU serial to Ethernet converters: AT command mode and data transmission mode. In AT command mode, users can use serial tools or configure various parameters of the converter through their MCU, and also support data transmission under AT commands.

Note: If a TCP connection is established before entering AT command mode, the connection will be closed when entering AT command mode.

When WIZ-DTU is in AT command mode, input the terminal detection command "AT\r\n" to its serial port. If the converter correctly receives "AT\r\n", it will reply with "OK\r\n".

When WIZ-DTU is in data transmission mode, any AT command input to the serial port is invalid. At this point, input "+++" to its serial port, and WIZ-DTU will switch to AT command mode.

Input rule for "+++": Three "+" must be sent continuously to the serial port at once, and there must be no other characters within 1 second before and after the "+++" in order for WIZ-DTU to respond correctly and switch to AT command mode.

Note: The default operating mode of WIZ-DTU at the factory is AT command mode.

AT command list

WIZ-DTU serial to Ethernet converters support serial AT command configuration parameters and also support data transmission in AT command mode. Therefore, AT commands can be roughly divided into two categories: AT configuration commands and AT data transmission commands.

All WIZSE products are using the same AT command Structure. Due to different solutions, it may have more than 1 serial channel for serial setup and communication.

The following are the information for WIZ-DTU:

WIZ-DTU

Number of Channels	Serial Type	Format	Name of Channel	Example
2	RS232	C[CH]	C1	AT+C1_PORT?
	RS485	C[CH]	C2	AT+C2_PORT?

Command name	Function	Attribute	Max length	Parameters
AT	Terminal detection	R	-	-
ECHO	Feedback	RW	1	0: Turn off echo display 1: Open echo (default)
DEBUGMSGEN	Debug information	RW	1	0: Close debugging information 1: Enable debugging information (default)
NAME	Equipment name	RW	15	Must be a number, letter, or a combination of both
PASS	converter password	RW	15	Must be a number, letter, or a combination of both. Default: admin
DEFAULT	Restore factory settings	W	15	When the parameter is "converter password", factory Reset
RESET	Save configuration and restart converter	W	15	When the parameter is' converter password ', restart the converter
EXIT	Save configuration and exit AT command mode	W	-	-
SAVE	Save Configuration	W	-	-
START_MODE	Next time starting the running mode	RW	1	0: AT command mode (default) 1: Data transparent transmission mode
C[CH]_OP	Working mode	RW	2	0: TCP Server(default) 1: TCP Client 2: UDP 16: Modbus RTU-TCP Server 17: Modbus RTU-TCP Client 18: Modbus RTU-UDP 32: Modbus ASCII-TCP Server 33: Modbus ASCII-TCP Client 34: Modbus ASCII-UDP
IP_MODE	How to obtain IP address	RW	1	0: Static retrieval (default) 1: DHCP acquisition
IP	converter IP address	RW	15	Default :192.168.1.88
MASK	converter subnet mask	RW	15	Default :255.255.255.0
GATEWAY	converter gateway	RW	15	Default :192.168.1.1
DNS	DNS server address	RW	15	Default :114.114.114.114
C[CH]_PORT	Local port number	RW	5	1 ~ 65535; Default: 5000
C[CH]_BIND	Bind local port number	RW	1	Valid for TCP client 0: Do not bind local port number (Default) 1: Bind local port number
C[CH]_DNSEN	DNS function	RW	1	0: Disable DNS function (Default) 1: Enable DNS function
C[CH]_CLI_IP1	Remote host IP address	RW	15	Default: 192.168.1.99
C[CH]_CLI_PP1	Remote host port number	RW	5	1~65535； Default: 5000
C[CH]_DOMAIN	Remote host domain name	RW	32	Default: www.w5500.com
C[CH]_RECONTIME	Reconnect time	RW	5	Valid for TCP client The value range is: 0~60000 Unit: ms Default: 0 (reconnect immediately)
NETBIOS	NetBIOS functionality	RW	1	0: Disable NetBIOS function (default) 1: Enable NetBIOS functionality
COM[CH]	Serial port parameters	RW	10	Default: 9,1,0,1,0
C[CH]_BAUD	Baud rate	RW	2	0: 1200； 1: 2400； 2: 4800 3: 9600； 4: 14400； 5: 19200 6: 38400； 7: 56000； 8: 57600 9: 115200 (default); 10: 128000 11: 234000； 12: 256000； 13: 468000 14: 921600； 15: 1152000
C[CH]_DATAB	Data bits	RW	1	0:7 digits 1: 8-bit (default)
C[CH]_STOPB	stop bit	RW	1	0: 0.5 1: 1 (default) 2: 1.5 3: 2
C[CH]_PARITY	check bit	RW	1	0: No verification (default) 1: Odd verification 2: Even verification
C[CH]_SER_C	Serial port flow control	RW	1	0: No flow control (default)
C[CH]_BUF_CLS	Clear serial port buffer	RW	1	Effective during TCP 0: Do not clear serial port buffer after connection (default) 1: Clear the serial port buffer after connection
C[CH]_SER_LEN	packet length	RW	4	The value range is: 0~2048 bytes Default: 0 (no packet)
C[CH]_SER_T	Serial port frame interval	RW	5	The value range is: 0~60000 Unit: ms Default: 0 (no packet)
C[CH]_IT	Timeout disconnect time	RW	5	Effective during TCP The value range is: 0~60000 Unit: ms Default: 0 (disable this feature)
C[CH]_TCPAT	Heartbeat detection time	RW	3	Effective during TCP The value range is: 0~255 Unit: 5s Default: 0 (disable this feature)
C[CH]_LINK_P	Connection password verification	RW	1	Valid on TCP Server 0: Do not verify password after TCP connection is established (default) 1: Verify password after establishing TCP connection
C[CH]_LINK_T	Connection establishment conditions	RW	1	Valid for TCP client 0: Establish connection immediately after power on (default) 1: Establish a connection after receiving data through the serial port
C[CH]_LINK_M	Send a message after connecting	RW	1	Valid in TCP mode 0: No message sent after connection establishment (default) 1: After establishing the connection, send the converter name 2: Send converter MAC address after connection establishment 3: Send converter IP address after connection establishment
C[CH]_SEND_NUM	The number of bytes sent by the serial port	R	-	Display range is 0 ~ 4294967295
C[CH]_RCV_NUM	Serial port received byte count	R	-	Display range is 0 ~ 4294967295
C[CH]_NETSEND	Number of bytes sent by the network port	R	-	Display range is 0 ~ 4294967295
C[CH]_NETRCV	Number of bytes received by the network port	R	-	Display range is 0 ~ 4294967295
PRE	List of default and current values	R	-	-
LIST	All command lists	R	-	-
RUNTIME	Equipment operation time	R	-	-
VER	converter firmware version number	R	-	-
MAC	converter MAC address	R	-	-
SN	Equipment serial number	R	-	-
TYPE	converter Type	R	-	-
WEB_PORT	Web port number	RW	5	1 ~ 65535;Default: 80
LINK	PHY connection status	R	-	0: PHY not connected 1: PHY connected
C[CH]_LISTEN	Establish TCP listening	W	-	-
C[CH]_CONNECT	Apply for TCP connection	W	-	-
C[CH]_TCP_STATUS	TCP connection status	R	-	0: TCP not connected 1: TCP Connected
C[CH]_UDP	Establish UDP communication	W	-	-
C[CH]_SEND	The number of bytes of data to be sent	W	4	Range: 0~2048 Default value: 0 (any length)
C[CH]_RLEN	Number of bytes of data to be received	R	-	-
C[CH]_RCV	Receive Data	W	4	Range: 0~2048 Default value: 0 (any length)
C[CH]_CLEAR	Clear the network port receiving cache	W	-	-
C[CH]_DISCON	Turn off TCP/UDP	W	-	-

AT Control commands

AT(Terminal check)

Command format	Parameters	Function Description
AT	Nil	Check the terminal
Response	OK\r\n
Example	Command: AT\r\n
	Response: OK\r\n

Description: In AT command mode, it only provides response check to ensure it is in AT command mode.

ECHO(Enable or disable echoing)

Command format	Parameters	Function Description
AT+ECHO?	Nil	Query current value
AT+ECHO= Parameters	0: Disable the echo function	Set new value
	1: Enable echo function (Default)
Response	[ECHO] Value is: AT+ECHO= Value\r\n OK \r\n
Example	Command: AT+ECHO?\r\n
	Response: [ECHO] Value is: 1\r\n OK\r\n

Description: The echo function refers to returning the data input from the serial channel as it is, and only exists in AT command mode. Enabling the echo function can help users configure converters more conveniently when using serial software. However, when configuring converters using embedded converters such as microcontrollers, enabling the echo function can cause trouble. It is recommended to disable it at this time.

DEBUGMSGEN(Debug message)

Command format	Parameters	Function Description
AT+ DEBUGMSGEN?	Nil	Query current value
AT+DEBUGMSGEN=Parameters	0: Close debugging information	Set new value
	1: Enable debugging information (Default)
Response	[DEBUGMSGEN] Value is: Value\r\n OK \r\n
Example	Command: AT+DEBUGMSGEN=1\r\n
	Response: [DEBUGMSGEN] Value is: 1\r\n OK\r\n

Description: This command is used to configure whether the converter should enable debugging information. Debugging information includes basic converter information and converter status change information, which will be output through the serial channel at startup for easy user viewing. If the user does not need this information, the debugging information output can be turned off through this command.

NAME(converter name)

Command format	Parameters	Function Description
AT+NAME?	Nil	Query current value
AT+NAME =Parameters	The total length is 15 characters, with the first character being a letter and the remaining 14 characters being any combination of letters, numbers, symbols' - 'or' _ '.	Set new value
	Default: converter P/N
Response	NAME] Value is: Value\r\nOK\r\n
Example	Command: AT+NAME=User1\r\n
	Response: [NAME] Value is: User1\r\nOK\r\n

Description: Users can customize converter names through this command.

Note: This command can be used in conjunction with the NetBIOS function. If the NetBIOS function is enabled, users can access the converter through the converter name in the browser. Please refer to the "AT+NETBIOS" command.

PASS(converter password)

Command format	Parameters	Function Description
AT+PASS?	Nil	Query current value
AT+PASS=Parameters	The converter password must be a combination of numbers, letters, or both, and cannot be empty. It is case sensitive and can be up to 15 bytes long	Set new value
	Default: admin
Response	[PASS] Value is:Value\r\nOK\r\n
Example	Command: AT+PASS=Admin1\r\n
	Response: [PASS] Value is: Admin1\r\nOK\r\n

Description: The converter password is used for restoring factory settings, verifying connection passwords, verifying web login passwords, and saving configurations and restarting the converter.

Note:
Factory reset function:
If you need to use the AT command to restore factory settings, you must enter the correct converter password. Please refer to the "DEFAULT" command for detailed functions.

Connection password verification function:
In order to improve communication security, WIZ-DTU converters provide a "connection password verification" function. When the converter communicates with the client as a TCP Server, if the "connection password verification" function is turned on, the client needs to enter the converter password through the network port after establishing a connection with the converter. If the password is correct, communication can begin; If the password is incorrect, you will be prompted to re-enter the correct password. For detailed functions, please refer to the "C 1 _LINK-P" command.

Web login password verification function:
If you need to log in to the converter configuration webpage, you must enter the correct converter password on the login verification page.

Save configuration and restart converter functionality:
To save the current configuration and restart the converter, the correct converter password must be entered to reset. After using this command, all sockets will be automatically closed. Please refer to the "RESET" command for detailed functions.

DEFAULT(Reset to factory default)

Command format	Parameters	Function Description
AT+DEFAULT=Parameters	converter password	Set new value
	default: admin
Response	OK\r\n
Example	Command: AT+DEFAULT=admin\r\n
	Response: OK\r\n

Description: The converter password must be completely correct in order to restore factory settings. The converter password can be queried and set through the "PASS" command.

RESET(Save and restart the converter)

Command format	Parameters	Function Description
AT+RESET=Parameters	converter password	Set new value
	Default: admin
Response	OK\r\n
Example	Command: AT+RESET=admin\r\n
	Response: OK\r\n

Description:

Save the current conﬁguration information
Restart the converter to make the conﬁguration information take eﬀect
When users need to directly enter data transmission mode during the next power on, they can conﬁgure the parameter value of the "AT+START-MODE=1\r\n" command to be 1, and then conﬁgure the "RESET" command
The converter password can be queried and set through the "PASS" command

EXIT(Save and exit command mode)

Command format	Parameters	Function Description
AT+EXIT	Nil	Execute immediately
Response	OK\r\n
Example	Command: AT+EXIT\r\n
	Response: OK\r\n

Description:

1 Save the current configuration information

2 Make the configuration information effective

3 Exit AT command mode and enter data transmission mode

SAVE(Save settings)

Command format	Parameters	Function Description
AT+SAVE	Nil	Execute immediately
Response	OK\r\n
Example	Command: AT+SAVE\r\n
	Response: OK\r\n

Description:

1 Save the current configuration information

2 Make the configuration information effective

Converter information configuration command

START_MODE(Start mode)

Command format	Parameters	Function Description
AT+START_MODE?	Nil	Query current value
AT+START_MODE=Parameters	0: AT command mode (default)	Set new value
	1: Data transparent transmission mode
Response	[START_MODE] Value is: Value\r\nOK\r\n
Example	Command: AT+START_MODE=1\r\n
	Response: [START_MODE] Value is: 1\r\nOK\r\n

Description: This command configures the running mode for the next startup. When users need to directly enter data transmission mode during the next power on, they can configure the parameter value of the "START_MODE" command to be 1, and then configure the "RESET" command.

C[CH]_OP(Operating mode)

Command format	Parameters	Function Description
AT+C[CH]_OP?	Nil	Query current value
AT+C[CH]_OP=Parameters	0: TCP Server(default) 1: TCP Client 2: UDP	Set new value
	16: Modbus RTU-TCP Server 17: Modbus RTU-TCP Client 18: Modbus RTU-UDP
	32: Modbus ASCII-TCP Server 33: Modbus ASCII-TCP Client 34: Modbus ASCII-UDP
Response	[C[CH]_OP] Value is:Value \r\nOK\r\n
Example	Command: AT+C1_OP=1\r\n
	Response: [C1_OP] Value is: 1\r\nOK\r\n

Description: When transmitting data in AT command mode, if you need to use this command to modify the operation mode, you need to first call the "DISCON" command to turn off TCP/UDP.

IP_MODE(IP configuration mode)

Command format	Parameters	Function Description
AT+IP_MODE?	Nil	Query current value
AT+IP_MODE=Parameters	0: Static retrieval (default)	Set new value
	1: DHCP acquisition
Response	[IP_MODE] Value is: Value\r\nOK\r\n
Example	Command: AT+IP_MODE=1\r\n
	Response: [IP_MODE] Value is: 1\r\nOK\r\n

Description: When selecting the static retrieval method, users need to set their own IP address, gateway, subnet mask, DNS server address, etc., or they can choose the default settings; When selecting DHCP mode, WIZ-DTU will dynamically obtain IP information through DHCP servers in the local area network.

IP(IP address)

Command format	Parameters	Function Description
AT+IP?	Nil	Query current value
AT+IP=Parameters	Default: 192.168.1.88	Set new value
Response	[IP] Value is: Value\r\nOK\r\n
Example	Command: AT+IP=192.168.1.88\r\n
	Response: [IP] Value is: 1\r\nOK\r\n

Description: The IP address is represented in IPv4 standard format, such as 192.168.1.88; Its maximum length is 15 bytes, and the range of values for each decimal number is from 0 to 255. This setting only takes effect when the IP configuration mode (IP_MODE) is set to 'Static IP Mode'.

MASK(Subnet mask)

Command format	Parameters	Function Description
AT+MASK?	Nil	Query current value
AT+MASK=Parameters	Default: 255.255.255.0	Set new value
Response	[MASK] Value is: Value\r\nOK\r\n
Example	Command: AT+MASK=255.255.255.0\r\n
	Response: [MASK] Value is: 255.255.255.0\r\nOK\r\n

Description: The subnet mask is represented in IPv4 standard format, such as 255.255.255.0, with a maximum length of 15 bytes. This setting only takes effect when the IP configuration mode (IP_MODE) is set to 'Static IP Mode'.

GATEWAY(Gateway)

Command format	Parameters	Function Description
AT+GATEWAY?	Nil	Query current value
AT+ GATEWAY =Parameters	Default: 192.168.1.1	Set new value
Response	[GATEWAY] Value is: Value\r\nOK\r\n
Example	Command: AT+GATEWAY=192.168.1.1\r\n
	Response: [GATEWAY] Value is: 192.168.1.1\r\nOK\r\n

Description: The gateway IP address is represented in IPv4 standard format, such as 192.168.1.1, with a maximum length of 15 bytes. This setting only takes effect when the IP configuration mode (IP_MODE) is in 'Static IP Mode'.

DNS(DNS server address)

Command format	Parameters	Function Description
AT+DNS?	Nil	Query current value
AT+DNS=Parameters	Default: 114.114.114.114	Set new value
Response	[DNS] Value is: Value\r\nOK\r\n
Example	Command: AT+DNS=114.114.114.114\r\n
	Response: [DNS] Value is: 114.114.114.114\r\nOK\r\n

Description: The DNS server address is represented in IPv4 standard format, such as 114.114.114.114, with a maximum length of 15 bytes. This configuration does not accept address inputs ending in ". 0" or ". 255", for example: xxx.xxx.xxx.0 or xxx.xxx.xxx.255.

C[CH]_PORT(Local port number)

Command format	Parameters	Function Description
AT+C[CH]_PORT?	Nil	Query current value
AT+C[CH]_PORT=Parameters	Range: 1~65535, Default: 5000	Set new value
Response	[C[CH]_PORT]Value is: Value\r\nOK\r\n
Example	Command: AT+C1_PORT=5000\r\n
	Response: [C1_PORT] Value is: 5000\r\nOK\r\n

Description: This command is used to configure the local port number. The converter operates in TCP Server and UDP mode with the corresponding number of channels, and communicates with the user converter through this port.

Note: Some protocols in the Ethernet protocol have default port numbers, which should be avoided. The default occupied port numbers are shown in the appendix.

C[CH]_BIND(Local port binding)

Command format	Parameters	Function Description
AT+C[CH]_BIND？	Nil	Query current value
AT+C[CH]_BIND=Parameters	0: Do not bind local port number (default)	Set new value
	1: Bind local port number
Response	[C[CH]_BIND] Value is: Value\r\nOK\r\n
Example	Command: AT+C1_BIND=1\r\n
	Response: [C1_BIND] Value is: 1\r\nOK\r\n

Description: When the converter operates in TCP Client mode on the corresponding serial channel, after binding the port number, WIZ-DTU will always use the local port number configured by the "C[CH]_PORT" command.

C[CH]_DNSEN(DNS enable)

Command format	Parameters	Function Description
AT+C[CH]_DNSEN?	Nil	Query current value
AT+C[CH]_DNSEN=Parameters	0: Disable DNS function (default)	Set new value
	1: Enable DNS function
Response	[C[CH]_DNSEN] Value is: Value\r\nOK\r\n
Example	Command: AT+C1_DNSEN=1\r\n
	Response: [C1_DNSEN] Value is: 1\r\nOK\r\n

Description: This setting takes effect only when the converter operates in TCP Client or UDP mode on the serial channel. After enabling DNS functionality, WIZ-DTU can access remote hosts using domain names. WIZ-DTU performs a DNS query upon each power-up.

Note: 1 If enabled and "C[CH]_DOMAIN" is set, the "C[CH]_CLI_IP1" command becomes invalid. The converter communicates with the host defined by "C[CH]_DOMAIN"; 2 If disabled and "C[CH]_CLI_IP1" is set, the "C[CH]_DOMAIN" command becomes invalid. The converter communicates with the IP defined by "C[CH]_CLI_IP1"; 3 To use DNS functionality, the converter IP information must be configured correctly. It is recommended to configure the converter in DHCP mode.

C[CH]_CLI_IP1(Remote host IP address)

Command format	Parameters	Function Description
AT+C[CH]_CLI_IP1?	Nil	Query current value
AT+C[CH]_CLI_IP1=Parameters	Default: 192.168.1.99	Set new value
Response	[C[CH]_CLI_IP1] Value is: Valuer\nOK\r\n
Example	Command: AT+C1_CLI_IP1=192.168.1.99\r\n
	Response: [C1_CLI_IP1] Value is: 192.168.1.99\r\nOK\r\n

Description: This command is only effective in TCP Client or UDP mode, used to configure the remote IP address for the corresponding serial channel of WIZ-DTU. The IP address must comply with IPv4 format, such as 192.168.1.99, as defined in the "IP" command.

Note: If the parameter value of the "DNSEN" command is 0, the parameters configured by the command are valid.

C[CH]_CLI_PP1(Remote host port number)

Command format	Parameters	Function Description
AT+C[CH]_CLI_PP1?	Nil	Query current value
AT+C[CH]_CLI_PP1=Parameters	Range: 1~65535, default: 5000	Set new value
Response	[C[CH]_CLI_PP1] Value is: Value\r\nOK\r\n
Example	Command: AT+C1_CLI_PP1=5000\r\n
	Response: [C1_CLI_PP1] Value is: 5000\r\nOK\r\n

Description: The converter operates in TCP Client and UDP modes with the corresponding number of channels.

Note: Some protocols in the Ethernet protocol have default port numbers, which should be avoided. The default occupied port numbers are shown in the appendix.

C[CH]_DOMAIN((Remote host name)

Command format	Parameters	Function Description
AT+DOMAIN?	Nil	Query current value
AT+C[CH]_DOMAIN=Parameters	Default: www.w5500.com The maximum length is 32 characters	Set new value
Response	[DOMAIN] Value is: Value\r\nOK\r\n
Example	Command: AT+C1_DOMAIN=www.w5500.com\r\n
	Response: [C1_DOMAIN] Value is: www.w5500.com\r\nOK\r\n

Description: This command configures the remote host's domain name. The setting takes effect when the corresponding converter channels operate in TCP Client or UDP mode.

Note: The command takes effect only when the "DNSEN" command's parameter value is set to 1.

C[CH]_RECONTIME(Reconnection interval)

Command format	Parameters	Function Description
AT+C[CH]_RECONTIME?	Nil	Query current value
AT+C[CH]_RECONTIME=Parameters	Default: 0 (immediate reconnection), value range is 0 to 60000, unit: ms	Set new value
Response	[C[CH]_RECONTIME] Value is: Value\r\nOK\r\n
Example	Command: AT+C1_RECONTIME=1000\r\n
	Response: [C1_RECONTIME] Value is: 1000\r\nOK\r\n

Description: The number of channels corresponding to the converter is valid when running in TCP Client and transparent mode. This command sets the time interval for the next connection request between WIZ-DTU and the remote host after the TCP connection is disconnected.

NETBIOS(NetBIOS)

Command format	Parameters	Function Description
AT+NETBIOS?	Nil	Query current value
AT+NETBIOS=Parameters	0: Disable NetBIOS function (default)	Set new value
	1: Enable NetBIOS functionality
Response	[NETBIOS] Value is:Value\r\nOK\r\n
Example	Command: AT+NETBIOS=1\r\n
	Response: [NETBIOS] Value is: 1\r\nOK\r\n

Description: The NetBIOS protocol can provide converter naming services within a local area network. After enabling the NetBIOS function, users can directly access WIZ-DTU's built-in web page by entering "http:// converter name" in the browser address bar. The converter name is configured using the "NAME" command.

Serial port information configuration command

COM[CH] (Serial parameters)

Command format	Parameters	Function Description
AT+COM[CH]?	Nil	Query current value
AT+COM[CH]=par1,par2, par3,par4,par5	par1: Baud rate parameter, refer to the "C[CH]_BAUD" command	Set new value
	par2: Data bit parameters, refer to the "C[CH]_DATAB" command
	par3: Parity bit parameter, refer to the "C[CH]_PARITY" command
	par4: Stop bit parameter, refer to the "C[CH]_STOPB" command
	par5: Serial port flow control parameters, refer to the "C[CH]_SER_C" command
Response	[COM1] Value is: value1,value2,value3,value4,value5\r\nOK\r\n
	Explain: Value1: Baud rate parameter value
	Value2: Data bit parameter value
	Value3: Parity bit parameter value
	Value4: Stop bit parameter value
	Value5: Serial port flow control parameter values
Example	Command: AT+COM1=9,1,0,1,0\r\n
	Response: [COM1] Value is: 9,1,0,1,0\r\nOK\r\n

Description: This command is used to configure or query 5 commonly used parameters of the related serial channel at once, or it can be configured or queried separately with the corresponding command.

C[CH]_BAUD(Baud Rate)

Command format	Parameters	Function Description
AT+C[CH]_BAUD?	Nil	Query current value
AT+C[CH]_BAUD=parameter	0:1200； 1:2400； 2:4800 3:9600； 4:14400； 5:19200 6:38400； 7: 56000； 8:57600 9:115200 (default); 10:128000 11:234000； 12:256000； 13: 468000 14:921600； 15:1152000	Set new value
Response	[C[CH]_BAUD] Value is: value\r\nOK\r\n
Example	Command: AT+C1_BAUD=9\r\n
	Response: [C1_BAUD] Value is: 9\r\nOK\r\n

Description: This command is used to configure or query the baud rate of the related serial channel.

C[CH]_DATAB(Data bit)

Command format	Parameters	Function Description
AT+C[CH]_DATAB?	Nil	Query current value
AT+C[CH]_DATAB=parameter	0:7bit 1:8bit (default)	Set new value
Response	[C[CH]_DATAB] Value is: value\r\nOK\r\n
Example	Command: AT+C1_DATAB=1\r\n
	Response: [C1_DATAB] Value is: 1\r\nOK\r\n

Description: This command is used to configure or query the data bits of the related serial channel.

C[CH]_STOPB(Stop bit)

Command format	Parameters	Function Description
AT+C[CH]_STOPB?	Nil	Query current value
AT+C[CH]_STOPB=parameter	0:0.5 1:1 (default) 2:1.5 3:2	Set new value
Response	[C[CH]_STOPB] Value is: value\r\nOK\r\n
Example	Command: AT+C1_STOPB=1\r\n
	Response: [C1_STOPB] Value is: 1\r\nOK\r\n

Description: This command is used to configure or query the stop bit of the related serial channel.

C[CH]_PARITY(Parity bit)

Command format	Parameters	Function Description
AT+C[CH]_PARITY?	Nil	Query current value
AT+C[CH]_PARITY=parameter	0:Nil (default) 1:Odd 2:Even	Set new value
Response	[C[CH]_PARITY] Value is: value\r\nOK\r\n
Example	Command: AT+C1_PARITY=0\r\n
	Response: [C1_PARITY] Value is: 0\r\nOK\r\n

Description: This command is used to configure or query the parity of the related serial channel.

C[CH]_SER_C(serial port flow control)

Command format	Parameters	Function Description
AT+C[CH]_SER_C?	Nil	Query current value
AT+C[CH]_SER_C =parameter	0: Disable flow control (default)	Set new value
Response	[C[CH]_SER_C] Value is: value\r\nOK\r\n
Example	Command: AT+C1_SER_C=0\r\n
	Response: [C1_SER_C] Value is: 0\r\nOK\r\n

Description: This command is used to configure or query the serial channel flow control of the related serial channel.

C[CH]_BUF_CLS(Clear Buffer if Connected)

Command format	Parameters	Function Description
AT+C[CH]_BUF_CLS?	Nil	Query current value
AT+C[CH]_BUF_CLS=parameter	0: Do not clear the serial port buffer after establishing a connection (default)	Set new value
	1: Clear the serial port buffer after establishing a connection
Response	[C[CH]_BUF_CLS] Value is: value\r\nOK\r\n
Example	Command: AT+C1_BUF_CLS=1\r\n
	Response: [C1_BUF_CLS] Value is: 1\r\nOK\r\n

Description: The converter is eﬀective when running in TCP mode and data transparent mode. If the connection suddenly disconnects during data exchange, some data may remain in the serial buﬀer and not be sent. This command can be used to determine whether to send this data after the connection is reestablished.

C[CH]_SER_LEN(Serial packaging Length)

Command format	Parameters	Function Description
AT+C[CH]_SER_LEN?	Nil	Query current value
AT+C[CH]_SER_LEN=parameter	The value range is: 0~2048 bytes, default: 0 (not specified Package)	Set new value
Response	[C[CH]_SER_LEN] Value is: value\r\nOK\r\n
Example	Command: AT+C1_SER_LEN=10\r\n
	Response: [C1_SER_LEN] Value is: 10\r\nOK\r\n

Description: This command sets the package length for each data transmission.

C[CH]_SER_T(Serial data packing Nagle wait time)

Command format	Parameters	Function Description
AT+C[CH]_SER_T?	Nil	Query current value
AT+C[CH]_SER_T=parameter	Value range: 0~60000, default: 0 (not subcontracted), unit: ms	Set new value
Response	[C[CH]_SER_T] Value is: value\r\nOK\r\n
Example	Command: AT+C1_SER_T=1000\r\n
	Response: [C1_SER_T] Value is: 1000\r\nOK\r\n

Description: This command sets the serial waiting time. After the waiting time passes, it gathers all the data and transmit in one data package.

C[CH]_IT(Inactivity timeout)

Command format	Parameters	Function Description
AT+C[CH]_IT?	Nil	Query current value
AT+C[CH]_IT=parameter	The time interval for timeout disconnection, with a value range of: 0~60000, unit: ms, default: 0 (disable this function)	Set new value
Response	[C[CH]_IT] Value is: value\r\nOK\r\n
Example	Command: AT+C1_IT=1000\r\n
	Response: [C1_IT] Value is: 1000\r\nOK\r\n

Description: The command is valid in TCP mode and data transparent mode. When the converter operates in TCP mode, whether as a server or client, there may be situations in which the other party has disconnected (e.g., due to a forced disconnection or network failure), and the converter is unaware of the disconnection message and continues to maintain an invalid connection. There will be an error when either party initiates communication, preventing data delivery.

Setting this parameter disconnects the TCP connection if the serial or Ethernet interface does not receive new data within a continuous timeout period during communication. Setting the value to 0 disables this function.

C[CH]_TCPAT(TCP keepalive interval)

Command format	Parameters	Function Description
AT+C[CH]_TCPAT?	Nil	Query current value
AT+C[CH]_TCPAT=parameter	Value range: 0~255, default: 0 (disable this function), unit: 5s	Set new value
Response	[C[CH]_TCPAT] Value is: value\r\nOK\r\n
Example	Command: AT+C1_TCPAT=1\r\n
	Response: [C1_TCPAT] Value is: 1\r\nOK\r\n

Description: The converter is effective when running in TCP mode and data transparent mode. When using TCP protocol for communication, converter will send a "heartbeat detection packet" to the other party at a fixed time period to test whether the connection exists after receiving or sending data communication. If no response is received after sending the 'heartbeat detection packet', the converter will automatically disconnect.

C[CH]_LINK_P(TCP password authentication)

Command format	Parameters	Function Description
AT+C[CH]_LINK_P?	Nil	Query current value
AT+C[CH]_LINK_P=parameter	0: Do not verify password after TCP connection is established (default)	Set new value
	1: Verify password after establishing TCP connection
Response	[C[CH]_LINK_P] Value is: value\r\nOK\r\n
Example	Command: AT+C1_LINK_P=1\r\n
	Response: [C1_LINK_P] Value is: 1\r\nOK\r\n

Description: The converter's serial channel is valid when running in TCP Server mode and data transparent mode. In order to improve communication security, the converter will provide a "Connection password veriﬁcation" function. When the converter communicates with the client as a TCP Server and the "Connection Password Veriﬁcation" function is turned on, the client needs to send the converter password as the ﬁrst packet of data after establishing a connection with the converter. If the password is correct, communication can begin; if it is incorrect, you will be prompted to re-enter the correct password. The converter password can be queried and set through the "PASS" command.

C[CH]_LINK_T(Connection Condition)

Command format	Parameters	Function Description
AT+C[CH]_LINK_T?	Nil	Query current value
AT+C[CH]_LINK_T=parameter	0: Establish connection immediately after power on (default)	Set new value
	1: Establish a connection after receiving data through the serial port
Response	[C[CH]_LINK_T] Value is: value\r\nOK\r\n
Example	Command: AT+C1_LINK_T=1\r\n
	Response: [C1_LINK_T] Value is: 1\r\nOK\r\n

Description: This command is valid in TCP Client mode and data transparent mode. This command is used to conﬁgure under what conditions the converter establishes a connection with TCP Server. When conﬁgured to establish connection after receiving data through the serial channel, the converter will not initiate a connection to the server until it gets the ﬁrst packet of data, and it will then immediately send a connection request to the server. After a successful connection, the converter's serial channel will send the ﬁrst data packet to the server and enter normal data transmission mode.

C[CH]_LINK_M(Send Hello Message)

Command format	Parameters	Function Description
AT+C[CH]_LINK_M?	Nil	Query current value
AT+C[CH]_LINK_M=parameter	0: Do not send messages (default)	Set new value
	1: Send converter name
	2: Send converter MAC address
	3: Send converter IP address
Response	[C[CH]_LINK_M] Value is: value\r\nOK\r\n
Example	Command: AT+C1_LINK_M=1\r\n
	Response: [C1_LINK_M] Value is: 1\r\nOK\r\n

Description: The command is valid in TCP Client mode and is valid in both data transparent mode and AT command transmission data mode. This command is used to conﬁgure the information that the converter sends immediately after the connection is established.

Management commands

C[CH]_SEND_NUM(Number of bytes sent via serial port)

Command format	Parameters	Function Description
AT+C[CH]_SEND_NUM?	Nil	Query current value
Response	[C[CH]_SEND_NUM] Value is: value\r\nOK\r\n
	Display range: 0~4294967295
Example	Command: AT+C1_SEND_NUM?\r\n
	Response: [C1_SEND_NUM] Value is: 2048\r\nOK\r\n

Description: This command is valid when the converter is in data transmission mode or AT command transmission mode.

C[CH]_RCV_NUM(Number of bytes received via serial port)

Command format	Parameters	Function Description
AT+C[CH]_RCV_NUM?	Nil	Query current value
Response	[C[CH]_RCV_NUM] Value is: value\r\nOK\r\n
	Display range: 0~4294967295
Example	Command: AT+C1_RCV_NUM?\r\n
	Response: [C1_RCV_NUM] Value is: 2048\r\nOK\r\n

Description: This command is valid when the converter is in data transmission mode or AT command transmission mode.

C[CH]_NETSEND(Number of bytes sent via network port)

Command format	Parameters	Function Description
AT+C[CH]_NETSEND?	Nil	Query current value
Response	[C[CH]_NETSEND] Value is: value\r\nOK\r\n
	Display range: 0~4294967295
Example	Command: AT+C1_NETSEND?\r\n
	Response: [C1_NETSEND] Value is: 2048\r\nOK\r\n

Description: This command is valid when the converter is in data transmission mode or AT command transmission mode.

C[CH]_NETRCV(Number of bytes received by the network port)

Command format	Parameters	Function Description
AT+C[CH]_NETRCV?	Nil	Query current value
Response	[C[CH]_NETRCV] Value is: value\r\nOK\r\n
	Display range: 0~4294967295
Example	Command: AT+C1_NETRCV?\r\n
	Response: [C1_NETRCV] Value is: 2048\r\nOK\r\n

Description: This command is valid when the converter is in data transmission mode or AT command transmission mode.

PRE(List preset values)

Command format	Parameters	Function Description
AT+PRE?	Nil	Query current value
	DEFAULT:
[NAME]:	WIZ-DTU
[PASS]:	admin
[IP]:	192.168.1.88
[MARK]:	255.255.255.0
[GATEWAY]:	192.168.1.1
[DNS]:	114.114.114.114
[WEB_PORT]:	80
[C1_DOMAIN]:	www.w5500.com
[C1_PORT]:	5000
[C1_BAUD]:	9
[C1_DATAB]:	1
[C1_PARITY]:	0
[C1_STOPB]:	1
[C1_SER_C]:	0
[C1_SER_T] :	0
[C1_SER_LEN]:	0
[C1_CLI_IP1]:	192.168.1.99
[C1_CLI_PP1]:	5000
[C2_DOMAIN]:	www,iwiznet.cn
[C2_PORT]:	5001
[C2_BAUD]:	9
[C2_DATAB]:	1
[C2_PARITY]:	0
[C2_STOPB]:	1
[C2_SER_C]:	0
[C2_SER_T] :	0
[C2_SER_LEN]:	0
[C2_CLI_IP1]:	192.168.1.99
[C2_CLI_PP1]:	5000
CURRENT:
[NAME] :	WIZ-DTU-xx
[PASS]:	admin
[IP]:	192.168.1.88
[MARK]:	255.255.255.0
[GATEWAY]:	192.168.1.1
[DNS]:	114.114.114.114
[WEB_PORT]:	80
[C1_DOMAIN]:	www.w5500.com
[C1_PORT]	5000
[C1_BAUD]:	9
[C1_DATAB]:	1
[C1_PARITY]:	0
[C1_STOPB]:	1
[C1_SER_C]:	0
[C1_SER_T] :	0
[C1_SER_LEN]:	0
[C1_CLI_IP1]:	192.168.1.99
[C1_CLI_PP1]:	5000
[C2_DOMAIN]:	www.w5500.com
[C2_PORT]:	5001
[C2_BAUD]:	9
[C2_DATAB]:	1
[C2_PARITY]:	0
[C2_STOPB]:	1
[C2_SER_C]:	0
[C2_SER_T] :	0
[C2_SER_LEN]:	0
[C2_CLI_IP1]:	192.168.1.99
[C2_CLI_PP1]:	5000
OK

LIST(List all commands)

Command format	Parameters	Function Description
AT+LIST?	Nil	Query current value
	[Control Command]
AT	AT+ECHO	AT+DEBUGMSGEN
AT+NAME	AT+PASS	AT+DEFAULT
AT+RESET	AT+EXIT	AT+SAVE
[converter Settings Command]
AT+START_MODE	AT+C1_OP	AT+IP_MODE
AT+IP	AT+MARK	AT+GATEWAY
AT+DNS	AT+C1_PORT	AT+C1_BIND
AT+C1_DNSEN	AT+C1_CLI_IP1	AT+C1_CLI_PP1
AT+C1_DOMAIN	AT+C1_RECONTIME	AT+NETBIOS
AT+C2_OP	AT+C2_PORT	AT+C2_BIND
AT+C2_DNSEN	AT+C2_CLI_IP1	AT+C2_CLI_PP1
AT+C2_DOMAIN	AT+C2_RECONTIME
[Management Command]
AT+C1_SEND_NUM	AT+C1_RCV_NUM	AT+C1_NETSEND
AT+C1_NETRCV	AT+C2_SEND_NUM	AT+C2_RCV_NUM
AT+C2_NETSEND	AT+C2_NETRCV	AT+PRE
AT+LIST	AT+RUNTIME	AT+VER
AT+MAC	AT+SN	AT+TYPE
AT+WEB_PORT
[Data Transfer Command]
AT+LINK	AT+C1_LISTEN	AT+C1_CONNECT
AT+C1_TCP_STATUS	AT+C1_UDP	AT+C1_SEND
AT+C1_RLEN	AT+C1_RCV	AT+C1_CLEAR
AT+C1_DISCON	AT+C2_LISTEN	AT+C2_CONNECT
AT+C2_TCP_STATUS	AT+C2_UDP	AT+C2_SEND
AT+C2_RLEN	AT+C2_RCV	AT+C2_CLEAR
AT+C2_DISCON
OK

RUNTIME(converter run time)

Command format	Parameters	Function Description
AT+RUNTIME?	Nil	Query current value
Response	[RUNTIME] Value is: value\r\nOK\r\n
	Format: ddd-hh-mm-ss, where "d" represents days, "h" represents hours, "m" represents minutes, and "s" represents seconds. The display range is 000-00-00-00~999-23-59-59
Example	Command: AT+RUNTIME?\r\n
	Response: [RUNTIME] Value is: 003-15-38-42\r\nOK\r\n

VER(Firmware version)

Command format	Parameters	Function Description
AT+VER?	Nil	Query current value
Response	[VER] Value is: value\r\nOK\r\n
Example	Command: AT+VER?\r\n
	Response: [VER] Value is: V1.0\r\nOK\r\n

MAC(Converter MAC Address)

Command format	Parameters	Function Description
AT+MAC?	Nil	Query current value
Response	[MAC] Value is: value\r\nOK\r\n
Example	Command: AT+MAC?\r\n
	Response: [MAC] Value is: 00.08.DC.11.12.13\r\nOK\r\n

SN(Equipment serial number)

Command format	Parameters	Function Description
AT+SN?	Nil	Query current value
Response	[SN] Value is: value\r\nOK\r\n
Example	Command: AT+SN?\r\n
	Response: [SN] Value is: 20190102-111213\r\nOK\r\n

TYPE(Equipment type)

Command format	Parameters	Function Description
AT+TYPE?	Nil	Query current value
Response	[TYPE] Value is: value\r\nOK\r\n
Example	Command: AT+TYPE?\r\n
	Response: [TYPE] Value is: WIZ-DTU-xx\r\nOK\r\n

WEB_PORT(Web port number)

Command format	Parameters	Function Description
AT+WEB_PORT?	Nil	Query current value
AT+WEB_PORT=parameter	Setting range: 1~65535, default: 80	Set new value
Response	[WEB_PORT] Value is: value\r\nOK\r\n
Example	Command: AT+WEB_PORT=80\r\n
	Response: [WEB_PORT] Value is: 80\r\nOK\r\n

Description: This port number is used to access the converter's web page conﬁguration site through a web browser, and it is not recommended to modify it. If conﬁgured with any port number other than 80, when accessing the converter through a browser, the address bar should enter "IP: Port", for example: 192.168.1.88:8000.

Note: Some protocols in the Ethernet protocol have default port numbers, which should be avoided. The default occupied port numbers are shown in the appendix.

Detailed description of AT data transmission command

LINK (PHY connection status)

Command format	Parameters	Function Description
AT+LINK?	Nil	Execute immediately
Response	[LINK] Value is: value\r\nOK\r\n
	Explanation: 0: PHY not connected 1: PHY connected
Example	Command: AT+LINK?\r\n
	Response: [LINK] Value is: 1\r\nOK\r\n

C[CH]_LISTEN(Establish TCP listening)

Command format	Parameters	Function Description
AT+C[CH]_LISTEN	Nil	Execute immediately
Response	OK\r\n
	TCP listening has been established
Error Response	Error Info\r\n
	The converter is not in TCP Server mode
Example	Command: AT+C1_LISTEN\r\n
	Response: OK\r\n

Description: The command is valid when the converter is running in TCP Server mode, which means that the command can only be configured correctly when the "C[CH]_OP" command parameter is "0", otherwise an error will be reported. It can be closed through the "DISCON" command.

Note: After conﬁguring this command, check whether the TCP connection has been established using the "C[CH]_TCP_STATUS" command.

C[CH]_CONNECT(Apply for TCP connection)

Command format	Parameters	Function Description
AT+C[CH]_CONNECT	Nil	Execute immediately
Response	OK\r\n TCP connection established
Error Response	Error Info\r\n
	The converter is not in TCP Client mode, or the connection has timed out
Example	Command: AT+C1_CONNECT\r\n
	Response: OK\r\n

Description: The command is valid when the converter is running in TCP Client mode. This command can only be configured correctly when the parameter of the "C[CH]_OP" command is "1", otherwise an error will be reported. After configuring this command, the converter immediately initiates a connection request to the TCP Server. If a TCP connection is not established after 3 seconds, an error message will be reported.

Note: After conﬁguring this command, check whether the TCP connection has been established using the "C[CH]_TCP_STATUS" command.

C[CH]_TCP_STATUS(TCP connection status)

Command format	Parameters	Function Description
AT+C[CH]_TCP_STATUS?	Nil	Query current value
Response	[C[CH]_TCP_STATUS] Value is: value\r\nOK\r\n
	0: TCP not connected
	1: TCP Connected
Example	Command: AT+C1_TCP_STATUS?\r\n
	Response: [C1_TCP_STATUS] Value is: 1\r\nOK\r\n

Description: This command is valid when running in TCP Server and TCP Client modes for the corresponding serial channel on the device. It is used for checking the TCP connection status.

C[CH]_UDP(Establish UDP communication)

Command format	Parameters	Function Description
AT+C[CH]_UDP	Nil	Query current value
Response	OK\r\n
	UDP communication has been established
Error Response	Error Info\r\n
	The converter is not in UDP mode
Example	Command: AT+C1_UDP\r\n
	Response: OK\r\n

Description: The converter operates in UDP mode. This command can only be configured correctly when the parameter of the "C[CH]_OP" command is "2", otherwise an error will be reported.

C[CH]_SEND(Number of bytes of data to be sent)

Command format	Parameters	Function Description
AT+C[CH]_SEND=parameter	Set the length of data to be sent from the serial port, Range: 0~2048, default: 0 (any length)	Set new value
Response	[C[CH]_SEND] Value is: value\r\nOK\r\n
Example1	Assuming the converter is in TCP mode and the TCP connection is normal:
	Command: AT+C1_TCP_STATUS?\r\n
	Response: [C1_TCP_STATUS] Value is: 1\r\nOK\r\n
	Command: AT+C1_SEND=5\r\n
	Response: [C1_SEND] Value is: 5\r\nOK\r\n
	Sending data to converter's serial port: 12345 Response: 5
Example2	Assuming the converter is in TCP mode and the TCP connection is abnormal:
	Command: AT+C1_TCP_STATUS?\r\n
	Response: [C1_TCP_STATUS] Value is: 0\r\nOK\r\n
	Command: AT+C1_SEND=5\r\n
	Response: [C1_SEND] Value is: 5\r\nOK\r\n
	Sending data to converter serial port: 12345 Response: 0

Description:

If the converter is running in TCP Server or TCP Client mode, before conﬁguring this command, it is necessary to check whether the TCP connection has been established by checking the result of the " TCP_STATUS" command.
After successfully conﬁguring the command, the serial port will receive the corresponding return value. The following serial data will be considered input data, sent as output data, then the data transmission exits and enters AT command mode.

3 If the speciﬁed sending length is 0, the serial port will default to pack the input data at 50ms frame intervals. Starting from the ﬁrst byte sent over the serial channel, if the channel's idle time exceeds 50ms, the data will be sent immediately. If the continuous byte length of the serial channel reaches 2048, the excess will be automatically discarded.

If the speciﬁed sending length is not 0, the serial channel will be packaged according to its length, and the speciﬁed length of characters will be immediately packaged and sent to the converter's serial channel. If it exceeds the speciﬁed length, the excess part will be automatically discarded; If it is less than the speciﬁed length, it will wait indeﬁnitely.
After the data is successfully sent from the module's network port, the module's serial channel will immediately output a reply message in the format of "len".len: The number of bytes of data successfully sent from the module's network port, which users can use to determine whether their data has been successfully sent.

C[CH]_RLEN(Number of bytes of data to be received)

Command format	Parameters	Function Description
AT+C[CH]_RLEN?	Nil	Query current value
Response	[C[CH]_RLEN] Value is: value\r\nOK\r\n Range: 0~2048
Example	Data to be received: abcdef
	Command: AT+C1_RLEN?\r\n
	Response: [C1_RLEN] Value is: 6\r\nOK\r\n

Description: This command queries the byte length of the data to be received in the receiving cache of the corresponding channel number network port.

C[CH]_RCV(Receiving data)

Command format	Parameters	Function Description
AT+C[CH]_RCV=parameter	Specify the length of data to be received from the serial port, Range: 0~2048, default: 0 (receive all)	Set new value and Execute immediately
Response	[RCV] Value is: value\r\nOK\r\ndata
	Explain: value: Number of received data bytes
	data: Received data
Example	Data to be received: abcdef
	Command: AT+C1_RCV=0\r\n
	Response: [C1_RCV] Value is: 6\r\nOK\r\nabcdef

Description:

If the converter is running in TCP Server or TCP Client mode, before conﬁguring this command, it is necessary to check whether the TCP connection has been established by checking the result of the " C[CH]_TCP_STATUS" command.
After successfully conﬁguring the command, the converter serial channel will output data from the network port receiving cache, then exit data reception and enter AT command mode.
The size of the cache received by the three network ports is 2048 bytes. If the total length of data received by the network port from the cache is 2048 bytes, the network port will stop receiving data.
If the length of the data in the cache received by the network port is less than the speciﬁed length set by the "C[CH]_RCV" command, it will not be received. Thus, the number of received data bytes is 0.

C[CH]_CLEAR(Clear the network port receiving cache)

Command format	Parameters	Function Description
AT+C[CH]_CLEAR	Nil	Execute immediately
Response	OK\r\n
Example	Command: AT+C1_CLEAR\r\n
	Response: OK\r\n

Description: If the converter does not require the network port to receive data from the cache, this command can be used to clear it.

C[CH]_DISCON(Turn off TCP/UDP)

Command format	Parameters	Function Description
AT+C[CH]_DISCON	Nil	Execute immediately
Response	OK\r\n
Example	Command: AT+C1_DISCON\r\n
	Response: OK\r\n

Description: Close the TCP or UDP connection of the converter.

Appendix

Default list of occupied ports in Ethernet protocol

Protocol	Port
Reserve	0
TCP port multi-channel server	1
Reserve	2
ECHO	7
Reserve	9
Reserve	11
Reserve	13
Network Status	15
FTP	20
FTP	21
TELNET	23
SMTP	25
Printer	35
Time server	37
Name server	42
Reserve	43
Login Host Protocol	49
DNS	53
DHCP	67
DHCP	68
TFTP	69
Gopler	70
Finger	79
HTTP	80
Remote TELNET	107
SUN	111
NNTP	119
NTP	123
SNMP	161
SNMP	162
IPX	213
Reserve	160~223

Overview of AT Command​

AT command Return values​

Enter AT command mode​

AT command list​

WIZ-DTU​

AT Control commands​

AT(Terminal check)​

ECHO(Enable or disable echoing)​

DEBUGMSGEN(Debug message)​

NAME(converter name)​

PASS(converter password)​

DEFAULT(Reset to factory default)​

RESET(Save and restart the converter)​

EXIT(Save and exit command mode)​

SAVE(Save settings)​

Converter information configuration command​

START_MODE(Start mode)​

C[CH]_OP(Operating mode)​

IP_MODE(IP configuration mode)​

IP(IP address)​

MASK(Subnet mask)​

GATEWAY(Gateway)​

DNS(DNS server address)​

C[CH]_PORT(Local port number)​

C[CH]_BIND(Local port binding)​

C[CH]_DNSEN(DNS enable)​

C[CH]_CLI_IP1(Remote host IP address)​

C[CH]_CLI_PP1(Remote host port number)​

C[CH]_DOMAIN((Remote host name)​

C[CH]_RECONTIME(Reconnection interval)​

NETBIOS(NetBIOS)​

Serial port information configuration command​

COM[CH] (Serial parameters)​

C[CH]_BAUD(Baud Rate)​

C[CH]_DATAB(Data bit)​

C[CH]_STOPB(Stop bit)​

C[CH]_PARITY(Parity bit)​

C[CH]_SER_C(serial port flow control)​

C[CH]_BUF_CLS(Clear Buffer if Connected)​

C[CH]_SER_LEN(Serial packaging Length)​

C[CH]_SER_T(Serial data packing Nagle wait time)​

C[CH]_IT(Inactivity timeout)​

C[CH]_TCPAT(TCP keepalive interval)​

C[CH]_LINK_P(TCP password authentication)​

C[CH]_LINK_T(Connection Condition)​

C[CH]_LINK_M(Send Hello Message)​

Management commands​

C[CH]_SEND_NUM(Number of bytes sent via serial port)​

C[CH]_RCV_NUM(Number of bytes received via serial port)​

C[CH]_NETSEND(Number of bytes sent via network port)​

C[CH]_NETRCV(Number of bytes received by the network port)​

PRE(List preset values)​

LIST(List all commands)​

RUNTIME(converter run time)​

VER(Firmware version)​

MAC(Converter MAC Address)​

SN(Equipment serial number)​

TYPE(Equipment type)​

WEB_PORT(Web port number)​

Detailed description of AT data transmission command​

LINK (PHY connection status)​

C[CH]_LISTEN(Establish TCP listening)​

C[CH]_CONNECT(Apply for TCP connection)​

C[CH]_TCP_STATUS(TCP connection status)​

C[CH]_UDP(Establish UDP communication)​

C[CH]_SEND(Number of bytes of data to be sent)​

C[CH]_RLEN(Number of bytes of data to be received)​

C[CH]_RCV(Receiving data)​

C[CH]_CLEAR(Clear the network port receiving cache)​

C[CH]_DISCON(Turn off TCP/UDP)​

Appendix​

Default list of occupied ports in Ethernet protocol​

Overview of AT Command

AT command Return values

Enter AT command mode

AT command list

WIZ-DTU

AT Control commands

AT(Terminal check)

ECHO(Enable or disable echoing)

DEBUGMSGEN(Debug message)

NAME(converter name)

PASS(converter password)

DEFAULT(Reset to factory default)

RESET(Save and restart the converter)

EXIT(Save and exit command mode)

SAVE(Save settings)

Converter information configuration command

START_MODE(Start mode)

C[CH]_OP(Operating mode)

IP_MODE(IP configuration mode)

IP(IP address)

MASK(Subnet mask)

GATEWAY(Gateway)

DNS(DNS server address)

C[CH]_PORT(Local port number)

C[CH]_BIND(Local port binding)

C[CH]_DNSEN(DNS enable)

C[CH]_CLI_IP1(Remote host IP address)

C[CH]_CLI_PP1(Remote host port number)

C[CH]_DOMAIN((Remote host name)

C[CH]_RECONTIME(Reconnection interval)

NETBIOS(NetBIOS)

Serial port information configuration command

COM[CH] (Serial parameters)

C[CH]_BAUD(Baud Rate)

C[CH]_DATAB(Data bit)

C[CH]_STOPB(Stop bit)

C[CH]_PARITY(Parity bit)

C[CH]_SER_C(serial port flow control)

C[CH]_BUF_CLS(Clear Buffer if Connected)

C[CH]_SER_LEN(Serial packaging Length)

C[CH]_SER_T(Serial data packing Nagle wait time)

C[CH]_IT(Inactivity timeout)

C[CH]_TCPAT(TCP keepalive interval)

C[CH]_LINK_P(TCP password authentication)

C[CH]_LINK_T(Connection Condition)

C[CH]_LINK_M(Send Hello Message)

Management commands

C[CH]_SEND_NUM(Number of bytes sent via serial port)

C[CH]_RCV_NUM(Number of bytes received via serial port)

C[CH]_NETSEND(Number of bytes sent via network port)

C[CH]_NETRCV(Number of bytes received by the network port)

PRE(List preset values)

LIST(List all commands)

RUNTIME(converter run time)

VER(Firmware version)

MAC(Converter MAC Address)

SN(Equipment serial number)

TYPE(Equipment type)

WEB_PORT(Web port number)

Detailed description of AT data transmission command

LINK (PHY connection status)

C[CH]_LISTEN(Establish TCP listening)

C[CH]_CONNECT(Apply for TCP connection)

C[CH]_TCP_STATUS(TCP connection status)

C[CH]_UDP(Establish UDP communication)

C[CH]_SEND(Number of bytes of data to be sent)

C[CH]_RLEN(Number of bytes of data to be received)

C[CH]_RCV(Receiving data)

C[CH]_CLEAR(Clear the network port receiving cache)

C[CH]_DISCON(Turn off TCP/UDP)

Appendix

Default list of occupied ports in Ethernet protocol