WAVESHARE RS232 485 WIFI ETH User Manual

5.1 WIRELESS NETWORKING SETTINGS The relevant AT commands are as follows:

Table wireless networking AT command list

Item

1

WMODE

2

WSSSID

3

WSKEY

4

WANN

5

WSLK

6

WAP

7

WAKEY

8

LANN

9

FAPSTA

Note Set/query WIFI operation mode (AP, STA) Set/query the SSID of the associated AP. Set/query the encryption parameters in WIFISTA mode. Set/query the network parameters of STA. Query the wireless connection status of STA Set/query parameters in WIFIAP mode. Set/query the encryption parameters in WIFIAP mode. Set/query module IP in AP mode Enable/disable module AP+STA mode

Table Socket related AT command list

Item

1

NETP

2

TCPB

Note Set/query network protocol parameters for TCPA Enable/disable TCPB function

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3

TCPPTB

4

TCPADDB

Set/query the port number of TCPB Set/query TCPB servers

The webpage configuration is as follows:

Figure Wireless Networking Settings webpage
The RS232/485 TO WIFI ETH (B) serial port server can be configured as either a wireless STA or an AP. There are AT commands and web page settings that can be set, as follows:
(1) AT command setting mode: it can be set by AT+WMODE, which can be set as AP or STA. Example: Set the WIFI serial server to STA mode, and after entering AT command mode, send the following command: Set WIFI serial port server to STA mode.
AT+WMODE=STA restart
AT+Z After restarting, the serial server works in STA mode.

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RS232/485 TO WIFI ETH (B) User Manual (2) The webpage is set as follows: For example, log in to the built-in webpage of the serial port server, enter the mode selection
page, and select the Station mode (set the WIFI serial port server to STA mode), as follows:

Figure Webpage Mode Setting WIFI Mode
After clicking OK, enter the module management page and restart to complete the work mode settings.
The module enables the AP+STA function, which can be set through the AT command (AT+FAPSTA) or customized to the factory default.
5.2 WIRELESS NETWORKING APPLICATIONS
5.2.1 WIRELESS NETWORKING APPLICATIONS (AP) The WIFI serial server is used as an AP, and other WIFI serial servers and computers can be
connected to this WIFI serial server as STA. At the same time, it can also be connected through the UART interface to the user device, as shown in the following figure:

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RS232/485 TO WIFI ETH (B) User Manual
Figure Access Point (AP)
The WIFI serial server operates in AP mode, and the above application can be set using the following AT command:
(1) Set the WIFI serial port server to AP mode AT+WMODE=AP
(2) Parameters under the WiFi serial server’s Access Point (AP) mode can be selected and configured based on your requirements or you can use the default parameters. Here’s an example of parameter settings:
At+WAP = 11bgn, waveshare-test, auto (optional) AT+WAKEY=WPA2PSK,AES,12345678 (optional) (3) Restart the WIFI serial server: AT+Z Complete the parameter setting. Note: 1. All settings set to the AT command need to enter the AT command mode (please refer to “RS232/485 TO WIFI ETH (B) AT instruction set” for details). 2. After the parameters are set, they need to be “restarted” to take effect, so as to refresh the original configuration information in the memory and restart the operation, which will not be described in detail later.
5.2.2 WIRELESS NETWORKING APPLICATION (STA) RS232/485 TO WIFI ETH (B) serial server is connected to other AP (such as routing in local area
network) as a STA to form a wireless network. All STAs regard this AP as the center of the wireless network, and the mutual communication between STAs is completed through the AP, as shown in the following figure:

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Figure Wireless networking application (STA)
The parameters of WIFI serial server are set as follows: (1) Set the working mode of the WIFI serial server:
AT+WMODE=STA (2) Set the SSID, encryption mode algorithm and password of the router to be connected (assuming that the routing SSID in the above figure is: Waveshare-TEST, encryption mode algorithm: WPA2PSK,AES, password: Waveshare), set as follows:
AT+WSSSID=Waveshare-TEST AT+WSKEY=WPA2PSK,AES,Waveshare (3) Restart the WIFI serial server: AT+Z Complete the parameter setting.
5.2.3 WIRELESS NETWORKING APPLICATION (AP+STA) The RS232/485 TO WIFI ETH (B) serial server can support both an AP interface and an STA
interface. When the AP+STA function is enabled, both the STA and AP interfaces are available. The STA interface of the serial server is connected with the router and connected with the server in the network through TCPB; At the same time, the AP interface can be connected by mobile phone /PAD (through TCPA connection). In this way, the servers in the network, such as TCPServer and mobile phone /PAD, can control the serial devices connected to the RS232/485 TO WIFI ETH (B) serial server or set the parameters of the serial server itself, as shown in the following figure:

Figure Wireless networking application (AP+STA)
The parameters of WIFI serial server are set as follows: 32

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(1) Enable WIFI serial server AP+STA function

AT+FAPSTA=on

(2) Effective after restoring factory settings

AT+RELD

(3) Set the WIFI serial server to STA mode, and at this time, the WIFI serial server AP interface is still valid:

AT+WMODE=STA

(4) Set the parameters for the WIFI serial server to connect to the route (assuming the route SSID in the figure above is WAVESHARE-WIFI-TEST, the encryption mode algorithm is WPA2PSK, AES, and the password is www.waveshare. com), as follows:

AT+WSSSID=WAVESHARE-WIFI-TEST

AT+WSKEY=WPA2PSK, AES, www.waveshare.com

(5) Set up SocketA and SocketB

Example of SocketA settings:

AT+NETP=TCP, Server, 8899,10.10.100.100.100

Set the IP and port number of the server to connect to (based on actual parameters)

SocketB settings example:

AT+TCPADDB=192.168.1.100

AT+TCPPTB=18899

(6) Restart the WIFI serial server:

AT+Z

Complete parameter settings.

Precautions:

When the AP+STA function is enabled, the STA port needs to be connected to other routers. Otherwise, the STA port will constantly scan the router, which will have a certain impact on the AP port, such as data loss. If the user determines that the STA cannot connect to the AP at this time, he can use the command to stop scanning the STA port:

AT+STTC=on/off

“On” means to scan the router, and “off” means not to scan. This command will not be saved after restarting.

AT+FSTTC=on/off

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RS232/485 TO WIFI ETH (B) User Manual This command can be saved and will take effect after restarting. The whole AP+STA application can also refer to our official website
FAQ:http://www.waveshare.com/Faq/45.html Web Page Configuration: Access the built-in web page, navigate to the wireless terminal settings
page, and enable the AP+STA functionality to configure AP+STA settings. As shown in the figure:

Figure Wireless networking application (AP+STA)
5.2.4 WIRELESS NETWORKING APPLICATION (AP, STA) The RS232/485 TO WIFI ETH (B) device’s wireless functionality can be configured in two modes:
as a wireless Station (STA) or as an Access Point (AP). Logically, it supports two wireless interfaces: one acting as a STA to connect to an existing wireless network, and the other interface serving as an AP, allowing other STAs to connect to the wireless network through this device.

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RS232/485 TO WIFI ETH (B) User Manual (6) Restart the WIFI serial server: The No.1 WIFI serial server works in STA mode and No. 2 works in AP mode: (1) set the No.1 WiFi serial server as STA.
AT+WMODE=STA For No.2 WIFI serial server, set it as AP.
AT+WMODE=AP (3) No.1 WIFI serial server is connected to AP(WIFI serial server 2) as a STA, so the SSID and password to be connected to WIFI serial server 1 are the AP parameters of WIFI serial server 2.
The SSID and password of No.2 WIFI serial server can be queried by using the following AT instructions:
AT+WAP AT+WAKEY You can also choose settings as required, or use default parameters. Examples of parameter settings for WIFI serial server 2 are as follows: At+WAP = 11bgn, waveshare-test, auto (optional) AT+WAKEY=WPA2PSK,AES,12345678 (optional) An example of parameter setting for No.1 WIFI serial server is as follows (set the SSID and password of WIFI serial server 2 corresponding to the connected AP parameters), as follows: AT+WSSSID=RS232/485 TO WIFI ETH (B)-TEST AT+WSKEY=WPA2PSK,AES,12345678 Consistent with the parameter setting example of WIFI serial server 2. (4) Restart the WIFI serial server: AT+Z Complete the parameter setting.

5.3 WIRED NETWORKING SETUP Related AT commands are as follows: Table related AT command list

Item

Note

1

WMODE

Set/query WIFI operation mode (AP, STA)

2

WSSSID

Set/query the SSID of the associated AP

3

WSKEY

Set/query the encryption parameters in WIFISTA mode

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4

WANN

5

WSLK

6

WAP

7

WAKEY

8

LANN

9

FEPHY

10

FVER

Set/query STA network parameters Query STA wireless connection status Set/query the parameters in WIFI AP mode Set/query the encryption parameters in WIFIAP mode
Set/query module IP in AP mode Enable/disable the module Ethernet port Set/query module software version (N-Ver, Z-Ver)

Item

1

NETP

2

TCPB

3

TCPPTB

4

TCPADDB

Table Socket related RT command list
Note Set/query TCPA network protocol parameters Enable/disable TCPB function Set/query TCPB port number: Set/query TCPB server

Webpage configuration as follows:

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Figure Enable/disable module Ethernet interface
The RS232/485 TO WIFI ETH (B) serial server offers a 100M Ethernet interface that allows users to achieve bi-directional communication between WiFi, serial, and Ethernet interfaces. Through this 100M Ethernet interface, seamless interaction is possible among the three interfaces, enabling effective data exchange. In terms of networking, the RS232/485 TO WIFI ETH (B) serial server’s Ethernet port can be configured as either a LAN port or a WAN port. Additionally, it supports both bridge mode and router mode to cater to different specific applications.
5.4 WIRED NETWORKING APPLICATION
5.4.1 WIRED NETWORKING APPLICATION (APLAN) When RS232/485 TO WIFI ETH (B) is used as AP, other computers or devices can be connected to
the serial port server as STA through RJ45 (i.e. network cable) and wireless mode, and a network is formed centering on the serial port server. The IP addresses of all devices in the network work in the same network segment and can communicate with each other, as shown in the following figure:

Figure Attached Private Local Area Network (APLAN)

Serial server parameter setting:

(1) Enable Ethernet port

AT+FEPHY=on

(2) Restore the factory settings to make the above settings take effect.

AT+RELD

Note that the AT+RELD command will not restore the above settings.

(3) Set the serial port server as AP

AT+WMODE=AP

(4) LAN parameters of serial port server need not be set by default, and IP address (DHCP gateway) and subnet mask of serial port server can also be modified as needed. The default values are used here:

AT+LANN=10.10.100.254,255.255.255.0 37

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RS232/485 TO WIFI ETH (B) User Manual (5) Restart the serial server to complete the parameter setting.
5.4.2 WIRED NETWORKING APPLICATION (APWAN) The RS232/485 TO WIFI ETH (B) serial server is used as AP, Ethernet port is set as WAN port, and
it is connected to the route that can access the external network, so the DHCP server function is enabled. The serial server is used as a secondary router, and a PC or other smart handheld device can access the Internet by connecting to the serial server AP. At this time, the default AP of the serial port server is usually RS232/485 TO WIFI ETH (B)_xxxx, which has no encryption and can be set through web pages or at commands.
After the serial server is connected to the AP, it obtains the IP address from the AP (as shown in Figure 192.168.1.10). The serial server itself forms a subnet (default is 10.10.100.254), and the devices on the Ethernet port are assigned addresses by the serial server (as shown in Figure 10.10.100.100, as shown below):

Figure Attached Private Wide Area Network (APWAN)

Serial server parameter setting:

(1) Enable Ethernet port

AT+FEPHY=on

(2) Set the serial server Ethernet port to work in WAN port mode

AT+FVEW=enable

(3) Restore factory settings for the above settings to take effect

AT+RELD

Note: The AT+RELD command will not restore the above settings.

(4) The serial server is operating in AP mode and DHCP is enabled (default, select settings).

AT+WMODE=ap

AT+DHCPDEN=on

(5) Considering security, you can modify the AP name and encryption parameters (optional).

AT+WAP=11BGN,B2-WIFI-TEST,Auto (select setting)

AT+WAKEY=WPA2PSK,AES,waveshare (select setting) 38

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RS232/485 TO WIFI ETH (B) User Manual (5) You can choose to set the LAN parameters of the serial server, including IP address (DHCP
gateway) and subnet mask (optional).
AT+LANN=192.168.2.1,255.255.255.0
Note: it is necessary to ensure that the set LANIP address cannot be in the same network segment as the WANIP address obtained by the serial server from the AP!
(6) Restart the serial server to complete the parameter setting.
5.4.3 WIRED NETWORKING APPLICATION (ROUTING) The RS232/485 TO WIFI ETH (B) serial server as STA, and the serial server works in router mode.
After the serial server is connected to the AP, it obtains the IP address from the AP (as shown in Figure 192.168.1.101). The serial server itself constitutes a subnet (10.10.100.254 by default), and the devices on the Ethernet interface are assigned addresses by the serial server (as shown in Figure 10.10.100.101). As shown in this figure, PC1 is in the subnet (NAT), so the connection can be initiated from PC1 and connected to PC2 (because RS232/485 TO WIFI ETH (B) works in routing mode), but PC2 cannot actively connect to PC1.

Figure Wired and Wireless Networking Application (Routing)
Serial server parameter setting: (1) Set the serial server software version to N-Ver.
AT+FVER=n (2) Enable Ethernet interface.
AT+FEPHY=on (3) Restore factory settings for the above settings to take effect.
AT+RELD Note that the AT+RELD command will not restore the above settings. (4) Set the serial server to STA AT+WMODE=STA

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RS232/485 TO WIFI ETH (B) User Manual (5) Set the SSID and password of the route to be connected to the serial server (according to the actual parameters of the route).
Example: AT+WSSSID=WAVESHARE-WIFI-TEST AT+WSKEY=WPA2PSK,AES,www.waveshare.com (6) Set the serial server LAN parameters, IP address (DHCP gateway) and subnet mask. Inquire about the IP obtained by the serial port server from the AP: AT+WANN Set the LAN parameters of the serial server to ensure that the LANIP address cannot be in the same network segment as the WAN IP address obtained by the serial server from the AP. In this case, since it is not in the same network segment, you can use the default instead of setting it. AT+LANN=10.10.100.254,255.255.255.0 (optional) (7) Restart the serial server to finish the parameter setting. Web Page Configuration: Access the built-in web page of the server, enter the Ethernet functional settings page, and within the Ethernet port mode configuration, set the Ethernet port mode to ‘n’.
As shown below:

After click “OK”, it reboots.

Figure Network Port Mode Setting

5.4.4 WIRED NETWORKING APPLICATION (BRIDGE) The serial server of RS232/485 TO WIFI ETH (B) is STA, and works in bridge mode. After the serial
server connecting to AP, the device of the Ethernet port gets the IP address from the AP (as shown in

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Figure 192.168.1.101). At this point, the entire network treats the serial server as if it were a transparent device. Communication between PC1 and PC2 is possible without any constraints, as if the serial server doesn’t introduce any limitations or obstacles in their interaction. However, for the RS232/485 TO WIFI ETH (B) serial server to communicate with other devices, it requires a static LAN IP address to be configured, such as the example address 192.168.1.10.

Figure Wired and Wireless Networking Application (Bridging):
6. PRODUCT FUNCTION DESCRIPTION
6.1 WORKING MODE RS232/485 TO WIFI ETH (B) has five working modes: (1) Transparent transmission mode (2) Serial Command Mode (3) HTTPDClient mode (4) ModbusTCP<=>ModbusRTU mode. (5) AT Command Mode Upon power-up, the serial server enters a pre-configure mode. By default, it enters transparent transmission mode. Switching between modes (1) to (4) can be configured using the serial server’s built-in web page or the AT command AT+TMODE.

In modes (1), (2), (3), and (4), the serial port sends “+++” followed by “a”. Once the serial server receives these sequences, it sequentially responds with acknowledgment codes “a” and “+ok”. This indicates the transition into mode (5), the AT command mode. To return from AT command mode to the original operational mode, the command AT+ENTM (with a carriage return) can be used.
Specific timing requirements for entering the AT command mode can be found in the “RS232/485 TO WIFI ETH (B) AT Command Set” documentation.

6.1.1 TRANSPARENT TRANSMISSION MODE RS232/485 TO WIFI ETH (B) supports the serial port transparent transmission mode. In this mode,
all the data that need to be sent and received are transparently transmitted between the serial port

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and WIFI/ Ethernet, without any parsing, so as to realize the data transmission between universal serial port devices and network devices.
In the transparent transmission mode, it can be completely compatible with the user’s original software platform. User equipment can basically support wireless data transmission without making software changes, as shown in the following figure:

Figure Transparent transmission function block diagram

6.1.2 SERIAL COMMAND MODE In this mode, users can send data to servers according to our protocol, and can send data to
different servers without restarting.

In this mode, when the RS232/485 TO WIFI ETH (B) serial server is used as UDPClient or TCPClient, users are allowed to send serial data to different servers, regardless of the number of Soc0ket.

The client’s MCU only needs to send data packets according to the format specified by our company, and the serial server will parse the received data. If the data conforms to the protocol, the serial server will send the parsed data to the designated server. If the data does not conform to the protocol, it will be treated as a waste package without sending it to the server.

The client MCU sends the data packet according to the following format, and after the WIFI serial server finishes parsing, only N bytes of data are sent to the target address. When data is returned, the data is directly output from the serial port without parsing.

Header Length 2
2 (n+m+5)

Function code
1

Table Serial command mode protocol

Reserved parameter area:

Target port

2

2

Target address

Data Checksum

m

n

1

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Always 0x550xaa Length:
The sum of all bytes from the start of the function code to the checksum (excluding the checksum). Note: The high byte comes first. Function code:
Bit0UDP0 TCP1 Bit1: (Long connection: 0) Note: Only long connections are supported at present. Bit2IP0 Domain name: 1) Bit7: (Simplified Protocol: 0; Full Protocol: 1) Note: Currently, only the simplified protocol is supported. Note: For Bit1, long connection, after sending data, the connection will be maintained until the target address is changed again. For Bit2, it represents whether the target address is IP or domain name, and if it is IP, the target address is 4 bytes; If it is a domain name, the length of the target address is the length of the entire domain name string (where the last byte of the target address is 0x00, that is, the end of the string, and the length of the domain name is indefinite). For Bit7, under the simplified protocol, the reply frame only contains data; Under the full protocol, the reply frame will have frame formats such as sending failure, waiting timeout, and responding device IP under UDP broadcast. Reserved parameter area: First byte: long connection, here 0x00. Second byte: reserved Target port: Little-endian format, with the low byte first. For example, the port number 33 would be represented here as 2100. Target address: If it is IP, it is 4 bytes, for example, 192.168.0.133 means 8500A8C0; If it is a domain name, the length of the address is uncertain, ending with ”. Data:

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RS232/485 TO WIFI ETH (B) User Manual The length is variable, and the maximum is 4*1024 bytes.
Checksum: Starting from the function code and continuing until the byte just before the checksum byte,
perform a summation checksum. The following are specific application examples:
Send data: 55aa000a00000021008500A8C0010f Length byte 000a: The length is n+m+5, here it is 10. Function code 00: UDP mode The destination IP address is 8500A8C0192.168.0.133. Data area 00: length is 1, Checksum calculation: 0x00+0x00+0x21+0x00+0x85+0x00+0xA8+0xC0+0x01 = 0x0F. Note: The serial command mode is a data transmission mode, so please pay attention to distinguish it from the AT command mode which can query or set the parameters of the serial server!
6.1.3 HTTPDCLIENT MODE In this mode, the user can send the data to the designated HTTP server, and RS232/485 TO WIFI
ETH (B) will automatically add an HTTP protocol header in front of the sent data, and the specific content of the protocol header can be set through AT instruction or webpage.
This mode is used for RS232/485 TO WIFI ETH (B) to transmit data to or obtain data from the HTTP server. After the user sets the specific content of HTTP header with AT command or webpage. Every time data is sent, RS232/485 TO WIFI ETH (B) will automatically package the sent data into HTTP protocol data and send it to the designated HTTP server. The data received from the server will be directly transmitted to the serial port without any processing. RS232/485 TO WIFI ETH (B) handles the complicated HTTP protocol, which is convenient for users to program the serial port without considering too many HTTP issues. The maximum size of data sent is 1000 bytes.

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Figure HTTPDClient functional block diagram
In GET mode, after the serial server receives the user’s serial data packet, the packaging format is as follows:
In POST mode, after the serial server receives the user serial data packet, the packaging format is as follows:

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Figure POST type data packaging mode

AT command setting:

Table HTTPDClient instruction list

No. Command

Note

1 HTPMODESwitching between new and old versions of HTTP header settings (HTTPDClient)

2 HTTPURL

Set/query the IP and port of HTTP servers in old version

3 HTTPTP

Set/query the HTTP protocol request in old version:

4 HTTPPH

Set/query the HTTP protocol header path in old version:

5 HTTPCN

To set/query the HTTP protocol header Connection in old version:

6 HTTPUA

To set/query the HTTP protocol header User-Agent in old version:

7 HTPSV

Set/query server address and IP (HTTPDClient) in new version

8 HTPTP

Set/query the request method (HTTPDClient) in new version

9 HTPURL

Setup/query request path (HTTPDClient) in new version

10 HTPHEAD

Set/query HTTP header (HTTPDClient) in new version.

11 HTTPSCEN

Set/query the connection mode of HTTPClient (long/short)

12 HTTPSCT

Set/query HTTPDClient short connection timeout (3-65535s)

The following are examples of specific applications: First, use AT command to set the related parameters of HTTP: If the data sent is 1234, Then the 80 port of test.waveshare.com will get the following data: POST/2.php?HTTP/1.1 Connection:keep-alive User-Agent:lwip1.3.2 Content-Length:4 Host:test.waveshare.com:80

1234 If the HTTP type is GET, the data received on port 80 of test.waveshare.com is

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RS232/485 TO WIFI ETH (B) User Manual GET/1.phpdata=1234HTTP/1.1 Connection :keep-alive User-Agent:lwip1.3.2 Host:test.waveshare.com:80
When the request mode is POST or PUT, the serial data will be added to the position behind the HTTP protocol header; When the request method is GET, the serial data will be added to the back of the protocol header path.
Users can customize the content of HTTP headers in the new definition mode, and can add, delete and modify the content of each HTTP header at will according to their own needs (if the HTTP request type is POST/PUT, RS232/485 TO WIFI ETH (B) will automatically add the Content-Length). The set instructions include AT+HTPMODE, AT+HTPSV, AT+HTPTP, AT+HTPURL and AT+HTPHEAD. Please refer to the chapter of AT Command Set for the specific command setting process. Similarly, there is a corresponding setting page in the webpage.
Note: The above definition method is called the old version definition method. In the new version of the setting mode, a new definition mode of HTTP header is added. If the HTTP header is set with AT command, please use “< < CRLF > >” instead of carriage return, and the carriage return problem is not needed when setting the built-in webpage. The webpage settings are as follows:
(1) set the HTTPDClient request type:

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Figure HTTPD Client request type
(2) Under the serial port and network configuration page, select the HTTPDClient mode as long/short.
If it is set to the short connection state, you can set the timeout of 3-65535(s).

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Figure HTTPDClient Short Connection Timeout Settings
The user can also set it through the AT command. (1) Set/query long/short connection of HTTPDClient, taking short connection as an example; AT+HTTPSCEN=short (2) Set/query timeout interval (3-65535) seconds in short connection mode; Take 3 seconds as an example; AT+HTTPSCT=3 HTTPD POST measured demonstration: 1Set the HTTPD Client POST parameter through the web page:

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2Open SSCOM serial communication assistant and send Json format through RS232/485 interface:
{ “apikey”: “tPmAT5Ab3j888”, “value1”: “33”, “value2”: “3”, “value3”: “22” } 3After sending successfully, the prompt in the red box will be returned:

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4Open a web page:https://pico.wiki/esp-chart.php , you can see the POST to the server data chart, as shown in the figure below:

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HTTPD GET measured demonstration: 1Set the HTTPD Client GET parameter through the web page:

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2Open SSCOM serial communication assistant and send it through RS232/485 interface. You need to get the latest value of a certain value on the webpage, for example, to get the latest value of value3:
variable=value3 3After sending successfully, the following is returned:

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4It is the same as that obtained through a web browser, as shown in the following figure:

6.1.4 MODBUSTCP<=>MODBUSRTU CONVERSION MODE This serial server supports ModbusTCP to ModbusRTU (ModbusASCII is not supported); The
network parameters of the module should correspond to those of the application software, the TCPserver should correspond to the TCPclient, and the ports should be configured the same, and the working mode should be ModbusTCP<=>ModbusRTU.

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Figure Modbus RTU<=>Modbus TCP
Set by AT command: AT+TMODE=modbus There are also corresponding settings pages in the webpage:

6.1.5 AT Command Mode In AT command mode, users can query the current status of WIFI serial server or set the
parameters of WIFI serial server by sending AT command.
6.2 WIRELESS CHARACTERISTICS

6.2.1 AUTOMATIC FREQUENCY SELECTION FUNCTION When RS232/485 TO WIFI ETH (B) works in STA mode, RS232/485 TO WIFI ETH (B) will
automatically adjust to the same channel as AP according to the wireless channel of AP, and access it.
When RS232/485 TO WIFI ETH (B) works in AP mode, it can be set to automatic frequency selection mode, so when RS232/485 TO WIFI ETH (B) is started, a better wireless channel will be selected according to the surrounding environment.

6.2.2 SECURITY MECHANISM The RS232/485 TO WIFI ETH (B) serial server supports a variety of wireless network encryption methods, which can fully guarantee the safe transmission of data, including:

1.WPA-PSK/TKIP

2.WPA-PSK/AES

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Note: The passwords of WPA-PSK and WPA2-PSK are 8-63 digits.
6.2.3 STA JOINS THE ROUTING FUNCTION The working mode of RS232/485 TO WIFI ETH (B) is set to Station mode. Click the “Search”
button in the “Wireless Terminal Settings” page, and a window will pop up to display the information of the surrounding AP. After selecting the router, you will return to the original page. At this time, the encryption mode and encryption algorithm have been filled in, and you only need to write the password as prompted.
6.2.4 STA ADDRESS BINDING FUNCTION RS232/485 TO WIFI ETH (B) supports the function of binding the BSSID of the destination
network during the networking process (as STA, during the AP connection process). According to the 802.11 protocol, different wireless networks can have the same network name (i.e. SSID/ESSID), but must correspond to a unique BSSID address (i.e. MAC address). Because illegal intruders can establish wireless networks with the same SSID/ESSID to connect STAs in the network to illegal APs, resulting in network leakage. So by binding BSSID addresses, STA can be prevented from accessing illegal networks, thereby improving the security of wireless networks.
6.3 SOCKET COMMUNICATION The working methods of SocketA include: TCP Server, TCP Client, UDP Server, and UDP Client.
Currently, SocketB supports TCP client and UDP Client.
When SocketA is configured as TCPServer, it can support up to a maximum of 24 TCP client connections in the TCP link. In a multi TCP link connection, data transmitted from TCP will be forwarded one by one to the serial port. The data coming from the serial port will be duplicated and forwarded to each TCP connection, resulting in multiple copies being sent to each connected TCP link. The specific data flow chart is shown as follows:

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Figure multi-TCP link data transmission diagram

SocketA settings: AT+NETP/AT+TCPTO/AT+TCPLK/AT+TCPDIS.

Table SocketA related AT command list

Item

Note

1

NETP

Set/query the network protocol parameters of

TCPA

2

TCPLK

Query whether the TCP link is established.

3

TCPTO

Set/query TCP timeout

4

TCPDIS

Connect/disconnect TCP (valid only for TCPClient)

SocketB setting: AT+TCPB/AT+TCPPTB/TCPADDB/TCPTOB/TCPLKB/TCPDIS

Table Socket B Related AT command list

Item

1

TCPB

Note Enable/disable TCPB function.

2

TCPPTB

Set/query the port number of TCPB

3

TCPADDB

Set/query the server address of TCPB.

4

TCPTOB

Set/query TCPB timeout

5

TCPLKB

Query whether the TCPB link has been

established

6

TCPDIS

Connect/Disconnect TCP

Please refer to the section “4.3.4. AT Command Set” in this manual for specific AT command related

parameters.

6.4 UART FRAMING MECHANISM

6.4.1 SERIAL PARAMETERS

Table Serial Parameters

Item Baudrate
Data bit Stop bit Checksum byte 485

Parameters 300, 600, 1200, 1800, 2400, 4800, 9600, 19200, 38400, 57600, 115200, 230400, 345600, 460800 5, 6, 7, 8 1, 2 None, Even, Odd NFC: No hardware flow control

Web page settings
Log in to the built-in webpage and set the serial port parameters on the “Serial Port and Network Settings” page, as follows:

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Figure Webpage Sets Serial Parameters
AT Command Settings If you need to change the WiFi serial server baud rate to 115200bps, use the following command: AT+UART=115200,8,1,None,NFC
6.4.2 UART FREE-FRAME MODE The default interval time for two bytes in the WiFi serial server is 10ms, which means that when
the interval time is greater than 10ms, a frame is considered complete. Using the example of sending data from a serial device to a serial server, let me explain the process of free-frame assembling in a WiFi serial server:
Assuming that n is the interval for free-frame assembling, measured in milliseconds, where T1 > n, T2 < n, T3 < n, T4 < n, T5 < n, T6 > n, then Byte1 to Byte5 are treated as a single frame of data, as illustrated

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Figure Switch cimmands timing order
The default interval time for two bytes in the WiFi serial server is 10ms, which means that when the interval time is greater than 10ms, a frame is considered complete. This interval time can be configured to 50ms using the following AT command to meet the customer’s requirements for serial port forwarding efficiency:
AT+FUARTTE=normal After the setting is completed, it is necessary to enable the above settings with the command of Restore Factory Settings: AT+RELD Note that the AT+RELD command will not restore the above setting. After testing, if it is set to 10ms, the time delay from WIFI->UART->WIFI loop is about 40 ~ 50ms if the data volume is not large. However, if the interval time is set to 10ms and the client’s MCU cannot guarantee sending the next byte within 10ms, the serial data might be fragmented. To restore the default free framing interval of 10ms, you can use the following AT command: AT+FUARTTE=fast After the setting is completed, you also need to use the Restore Factory Settings command to enable the above settings. For specific UART automatic framing operations, please refer to the “AT Command Set” section of this manual, which provides information on the UARTF/UARTFT/UARTFL commands.
6.4.3 UART AUTOMATIC FRAMING MODE For fixed-length data frames on the serial port, you can enable the UART automatic framing
function, and set the automatic framing trigger time and trigger frame length. RS232/485 TO WIFI ETH (B) will send the data from the serial port.
The received data is automatically framed and forwarded to the network.

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RS232/485 TO WIFI ETH (B) User Manual 1. Automatic framing trigger frame length: refers to RS232/485 TO WIFI ETH (B) receiving the
specified number of bytes from the serial port, composing a data frame and forwarding it to the network.
2. Automatic framing trigger time: It means that RS232/485 TO WIFI ETH (B) will forward the received data to the network if the data received from the serial port is less than the length of the automatic framing trigger frame within the trigger time.
The time of automatic framing starts from the first byte received by the WIFI serial port server from the serial port. As shown in the figure below:
Figure automatic framing trigger frame length

Figure automatic framing departure time
The specific UART automATic framing operATion can be set through the “serial port and network settings-> serial port automATic framing settings” section of the built-in webpage of WIFI serial port server or by using the at command. For the at command settings, please refer to the introduction of UARTF/UARTFT/UARTFL commands in the “at command set” chapter of this manual.
6.5 PASSWORD AUTHENTICATION WHEN TCP ESTABLISHES CONNECTION This function is only applicable to RS232/485 TO WIFI ETH (B) as a TCPServer. When the
TCPClient connects to RS232/485 TO WIFI ETH (B), RS232/485 TO WIFI ETH (B) will authenticate every connected TCP.

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After connecting via TCPClient, the first data to be sent should be the web password of the RS232/485 TO WIFI ETH (B), followed by a carriage return and line feed. By default, the password of RS232/485 TO WIFI ETH (B) is admin, so the first data sent by TCPClient should be “0x610x640x6D0x690x6e0x0D0x0A” (hexadecimal). If the password is correct, RS232/485 TO WIFI ETH (B) returns “OK”, otherwise returns “NO” and disconnects.
This function can be enabled or disabled in “TCP connection password verification” in the webpage.

Figure RFC2217 automatic baud rate
6.6 DESCRIPTION OF RFC2217 PROTOCOL The length of the protocol is 8 bytes, and the specific content of the protocol is as follows. The
numerical value of the example is in HEX format:

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Attachment: Explanation of the meaning of serial port parameter bit.

Table Query Instructions

Name

Header

Baudrate

Bits

Checksum

Bytes

3

3

1

1

Reduce false Three bytes represent a Different bits The checksum of the

Note

positives bybaud rate value, with therepresent differentfirst four bytes, ignoring

three bytes high byte first

meanings,

any carry-over

See attached table

Example

55AA55

01C200

83

46

(115200, N, 8,1)

Example

55AA55

002580

83

28

(9600,N,8,1)

Form query reply instruction

No. Name

1

Header

2

Length

Bytes 1 2

3 Command

code

4 AP number

5

SSID1

6 Terminator

7

Signal

strength 1

8 Terminator

…

…

M

SSIDn

M+1 end mark M+2 Signal
strength n M+3 Terminator M+4 Checksum Bit

1
1 Indefinite length
1 1
2 … Indefinite length 1 1
2 1

Note Fixed value 0xFF The total number of bytes after the length (excluding the length itself) and before the checksum byte (excluding the checksum
byte). Command type, and the reply instruction corresponding to the
query instruction is 0x81. Number of currently detected APs
The SSID of router 1.
The SSID terminator for router 1, with a fixed value of 0x00. The signal strength of router 1 network, ranging from 0 to 100,
corresponds to an actual value of 0% to 100%. Terminator of signal strength 1, 0x0D, 0x0A. ……… The SSID of router n.
SSID terminator of router n, fixed value 0x00. The signal strength of router N network ranges from 0 to 100,
and the corresponding actual value is 0% to 100%. The terminator of signal strength n, 0x0D, 0x0A.
The cumulative sum of all bytes after the header (excluding the header) and before the checksum (excluding the checksum).

6.7 FAST NETWORKING PROTOCOL

When the WIFI serial server is operating in AP mode, it will open a UDP port for receiving fast

networking protocol commands, with a port number of 49000. The mobile phone can be directly

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connected to the WIFI network of the WIFI serial port server, and can query the SSID information list and set the router SSID and password through the commands under UDP protocol. After the setting is completed, the WIFI serial server will automatically restart and connect to the router, and it will work in STA mode at this time.
Protocol format description:
Table query instruction

Number of

No.

Name

bytes

Note

1

Header

1

Fixed value 0xFF

2

Length

2

The number of bytes after the length (excluding the length) and

before the checksum (excluding the checksum).

Command

3

code

1

Command type, 0x01 is a query instruction

Checksum

The cumulative sum of all bytes after the header (excluding the

4

1

byte

header) and before the checksum (excluding the checksum).

Table Query Reply Instructions

No. Name

Bytes

Note

1

Header

1

Fixed value 0xFF

2

Length

2

All bytes after the length (excluding the length) and before the

checksum byte (excluding the checksum byte)

3

Command 1

Command type, and the reply instruction corresponding to the

code

query instruction is 0x81

4

AP number 1

The number of APS currently searched

5

SSID1

Indefinite The SSID of router 1

length

6

end

1

Router 1′ s SSID terminator, fixed value 0x00

character

7

Signal

1

The signal strength of router 1 network ranges from 0 to 100, and

strength 1

the corresponding actual value is 0% to 100%

8

End

2

Terminator of signal strength 1, 0x0D, 0x0A

character

…

…

…

………

M

SSIDn

Indefinite The SSID of router n

length

M+1 End

1

SSID terminator of router n, fixed value 0x00

character

M+2 Signal

1

The signal strength of router N network ranges from 0 to 100, and

strength n

the corresponding actual value is 0% to 100%

M+3 End

2

The end character of signal strength n, 0x0D, 0x0A

Character

M+4 Checksum 1

The cumulative sum of all bytes after the header (excluding the

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byte

header) and before the checksum byte (excluding the checksum

byte).

Example: Mobile phone sent to WIFI serial server (hexadecimal number): FF00010102. WIFI serial server returns to mobile phone (hexadecimal number):
FF00148102544553543100400D0A 544553543200370D0A1F Note: The mobile phone sends a query instruction to the WIFI serial server to query the router
related information. The information returned by the WIFI serial server to the mobile phone is: there are two routers, the SSID of router 1 is “TEST1” and the signal strength is 64%; Router 2 has an SSID of “TEST2” and a signal strength of 55%.
Note: The router information replied by the WIFI serial server is sorted according to the signal strength.
Table setting instruction

No. Name

1

Header

2

Length

3

Command

code

4

Reserved

byte

5

SSID

6

Separator

7

Password

8

Checksum

byte

Bytes 1 2
1

Note Fixed value 0xFF The number of bytes after the length (excluding the length) and before the checksum (excluding the checksum). Command type, 0x02 is the setting command.

1

The default is 0x00.

Indefinite length 2 Indefinite length 1

The SSID of the router.
SSID terminator, fixed values 0x0D, 0x0A. The password of the router.
The cumulative sum of all bytes after the header (excluding the header) and before the checksum byte (excluding the checksum byte).

No. Name 1 Header 2 Length
3 Command code
4 Checksum value
5 Checksum

Table setting reply instruction

Bytes Note 1 Fixed value 0xFF 2 All bytes after the length (excluding the length) and before the
checksum bye (excluding the checksum byte). 1 Command type, 0x82 is the reply instruction corresponding to the
setting instruction. 1 The checksum result of SSID, if the network value corresponding to this
SSID can be found, is 0x00, if not, the value is 0x00. 1 The checksum result of the password, if the password format is correct,

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value

the value is 0x00, if it is incorrect, the value is 0x00.

6 Checksum 1 The cumulative sum of all bytes after the header (excluding the header)

Byte

and before the checksum byte (excluding the checksum byte).

Example: The mobile phone is sent to the WIFI serial server (hexadecimal number): ff000f020054455354310d0a313233343536ce. WIFI serial server returns to mobile phone (hexadecimal number): FF000382010187. Note: The mobile phone sends a setting instruction to the WIFI serial server, setting the SSID as “TEST1” and the password as “123456”. The information returned by the WIFI serial server to the mobile phone is that there is a network with the SSID of “TEST1” and the password format is correct.
6.8 LOCAL AREA NETWORK SEARCH
RS232/485 TO WIFI ETH (B) supports local network search functionality. This means that when RS232/485 TO WIFI ETH (B) is connected to a wireless router, users can obtain the IP address of the current local network serial port server for RS232/485 TO WIFI ETH (B) by sending a UDP broadcast to a specific fixed port. This enables device discovery and communication within the local network.
You can also directly connect the AP of RS232/485 TO WIFI ETH (B) to send the search instruction, as shown in the following figure:

Figure LAN search block diagram
Search protocol process: 1. On another device in the local area network, send the search instruction “www.waveshare.com” through UDP broadcast (broadcast address: xx.xx.255, port: 48899). 2. After RS232/485 TO WIFI ETH (B) receiving the password, if the password is correct, RS232/485 TO WIFI ETH (B) enters the configuration mode and sends IP,MAC,MID and VER to the address (unicast, source port).

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Table search reply content

Item

Content

IP address xxx.xxx.xxx.xxx

MAC address xxxxxxxxxxxxxx

MID

Version number

If no setting command is received within 30 seconds after RS232/485 TO WIFI ETH (B) enters configuration mode, RS232/485 TO WIFI ETH (B) will exit configuration mode, and the user needs to resend the search command word to enter configuration mode. 3. Users can set and read parameters/states by sending network AT commands to this port. The AT command format is the same as the serial port AT command.
Note: The search tool and RS232/485 TO WIFI ETH (B) must be on the same LAN. If multiple STAs are connected to a router, the computer running the search tool is also connected to that router. This search tool can find all the STAs.

6.9 REGISTRATION PACKET FUNCTION
This function only applies to RS232/485 TO WIFI ETH (B) as TCPClient. The function of registered CLOUD is to send a registration package consisting of device ID and communication password when RS232/485 TO WIFI ETH (B) is connected to the server, and the registration package information is correct, and the server returns. Registration success information, RS232/485 TO WIFI ETH (B) access to transparent cloud platform. The USR (User-defined Registration Package) function allows users to customize the content of the registration package, and the length is limited to 40 characters (supported in UDPClient mode, and the user-defined registration package is added before each data packet is sent). There are two ways to register MAC function: one is to send registration information when connecting to the server for the first time; The other is to add registration information in front of the data sent each time. There is only one way to register CLOUD, that is, when connecting to the server, send a registration package to join Transparent Cloud.

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Figure data carrying registration package diagram
Parameters related to this function are set in the “serial port and other settings” section of the webpage, which is disabled by default. The relevant instruction settings are as follows:
Table Registration Package Command List
No. Command Note 1 REGEN Set registration packet type 2 REGTCP Registration packet setting 3 REGCLOUD Set/query transparent cloud account and password 4 REGUSR Set/query user-defined registration package content
6.10 CUSTOMIZED HEARTBEAT PACKETS In the network transparent transmission mode, users can choose to turn on the custom
heartbeat packet function, and heartbeat packet can choose to send it to the network server or the serial port device. The schematic block diagram is as follows:

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Figure Custom heartbeat packet Functional Block Diagram
The main purpose of sending to the network is to keep the connection with the server, and at the same time, let the server that has been idle for a long time (not sending data to the server for a long time) check whether the current connection status is valid.
In applications where servers send fixed query instructions to devices, in order to reduce frequent interaction, users can choose to send heartbeat packets (query instructions) to the serial device end instead of sending query instructions from the server.
To enable the custom heartbeat packet function, the AT command setting steps are as follows: (1) Enable the function of sending heartbeat packets
AT+HEARTEN=on (2) Set the type of heartbeat packet sending direction (NET or COM), for example, set the heartbeat packet to be sent to the network server.
AT+HEARTTP=NET (3) Set the heartbeat packet data (up to 40 bytes), for example, to set the data to the string www.waveshare.com, you need to first convert it to a hexadecimal string as
7777772E7761766573686172652E636F6D AT+HEARTDT=7777772E7766573686172652E636F6D (4) Set the interval time for sending heartbeat packets, with a range of 1-65535s and a default of 30s. For example, set the transmission interval to 30 seconds.

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AT+HEARTTM=30 In addition to the above settings, you should also set the network connections such as socketA and socketB, please refer to Section 2.4. After setting, restart the serial server. When the socket or socket is connected to the server, if there is no data transmission in the serial port of the device within 30 seconds, the serial server will send the string www.waveshare.com to the server. The related instructions are set as follows:
Table heartbeat packet instruction list

No. Command

Note

1 HEARTEN Query/set whether to turn on heartbeat packet function.

2 HEARTTP

Query/set heartbeat packet sending method.

3 HEARTDT

Query/Set heartbeat packet Data

4 HEARTTM Query/Set the sending heartbeat packet interval.

6.11 SOCKET DISTRIBUTION FUNCTION
In transparent transmission mode, the socket distribution function is enabled, and the client’s MCU only needs to send data packets according to this protocol format, and the serial server will parse the received data packets. If it meets the protocol format, the serial server will send the parsed data to the specified socket connection; If the data does not conform to the protocol format, the corresponding error code will be returned and will not be sent to the specified socket connection. At the same time, the data sent by the network will be packaged by the serial server according to the protocol format and sent to the serial device.
(1) serial device to module data format The client MCU sends data packets according to the following format. After the module is parsed, only N bytes of data are sent to the specified Socket connection. When data is returned, the data is directly output from the serial port without parsing.
Table Serial port sending format

Header Length Parameter area Data Checksum

3 2(n+2)

2

n

1

Header: Always 0x550xFD0xAA
Length: The sum of all bytes from the parameter area (including the parameter area) to the checksum
(excluding the checksum). High byte first Parameter area:
The first byte: common parameter area, which is the connection serial number (SocktA or SocketB); If the serial number is 0x61, it represents all the connection objects sent to SocketA, and if it is 0x62, it represents the connection objects sent to SocketB.
Second byte: spare parameter area, which is 0x00 by default. The common parameter area is in front, and the spare parameter area is in the back. Data:

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The length is variable, and the length of the whole data packet is not more than 4096 bytes. Checksum:
Starting from the parameter area (including the parameter area), and counting up to the byte before the checksum byte, calculate the sum and take the last byte as the checksum byte. The following are specific application examples:
55FDAA00036100CC2DHex Among them, Length byte 0003: length is 3. Parameter byte: 6100: Send data to socketA connection. Data area CC: The data sent is “0xCC”. Checksum calculation: 61+00+CC=2D. (2) Data format from module to serial port device When data (n bytes) is sent from the network, the module sends the data packet to the serial device according to the following format; In addition, when the serial device sends data to the module, if there is an error in sending, it will also reply to the serial device according to this format.
Table Serial Port Sending Format

Header Length Parameter area Data Parity bit

3

2(n+2) 2

n

1

Header Always 0xAA0xFD0x55 Length: The sum of all bytes from the parameter area (including the parameter area) to the sum check (excluding the sum check). High byte first Parameter area: The first byte: common parameter area, which is the connection serial number (socket or socket b); The data returned for SocketA is 0x61, and the data returned for SocketB is 0x62. The second byte: spare parameter area, and the seventh bit indicates whether the reply frame is data returned by the network or the module. (1: module returns data; 0: network returns data). Data: If it is network data, copy the data directly to the location; The length is variable, and the length of the whole data packet is not more than 4096 bytes. If it is the data replied by the module, the corresponding operation reply code is returned. The specific operation reply code is as follows:
Table Operation reply code

No. Return code Description

Note

1 0x00

Header error

2 0x01

Data length error

3 0x02

Parameter error

4 0x04

Checksum error

5 0x10

Sending failed (parameters correct but sending failed)

Checksum:

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Starting from the parameter area (including the parameter area) and before the checksum byte, add and take the last byte as the checksum byte. The following is a specific application example: AAFD5500036100CC2D (Hex)
Among them, length byte 0004: is length 4 Reference number 6100:61- SocketA data 00- Network sends to serial devices Data area CC: Data sent from network socket A Checksum calculation: 61+00+CC=2D Taking Socket as an example, the serial port device sends abc to Socket, and the network-side Socket sends data 123 to the serial port device, as shown below:

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Figure Socket Distribution Protocol

TIMEOUT REBOOT FUNCTION
The “timeout reboot” here means no data restart. In transparent transmission mode, when the timeout restart feature is enabled, if the module’s WiFi is not connected or if WiFi is connected but there is no communication within the set time frame, the module will be restarted. To enable the timeout restart feature, follow these AT command setup steps:
(1) Enable timeout reboot function AT+TIMEOUTEN=on (2) Set the timeout reboot time, which can be set in the range of 60-65535s, and the default is 3600s. Take 100s as an example; AT+TIMEOUTT=100 Parameter settings are complete, and they will take effect after the module is restarted. For example: After setting AT+TIMEOUTT=100, if the module remains without a WiFi connection within 100 seconds or if there’s a WiFi connection but no communication, the module will reboot. If communication occurs or there is a connection within the 100 seconds, the timer will reset.

No.

Command

1

TIMEOUTEN

2

TIMEOUTT

Table Timeout Reboot Command List
Note Enable/disable timeout reboot function Query/set timeout reboot time

6.13 TIMED REBOOT FUNCTION
“Timed reboot is equivalent to “reboot after set time”, in non-serial command mode, when this function is enabled, the module will use the internal clock to time, and the module will reboot forcibly after the set time.
Turn on the timed reboot function. The AT command setting steps are as follows: (1) Turn on the timed reboot function AT+REBOOTEN=on (2) Set the timed reboot time, which can be set from 1 to 720 h, and the default is 24 h; (3) For example: set 200h and restart the module once, with the following command. The AT+REBOOTT=200 parameter setting is finished and takes effect after the module restarts. After taking effect, the module restarts every 200 hours.
Table Scheduled Reboot Command List

No.

Command

1

REBOOTEN

2

REBOOTT

Note Enable/Disable the scheduled reboot function Query/Set the scheduled reboot time

6.14 MOD BUS POLLING 72

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RS232/485 TO WIFI ETH (B) User Manual (1) The webpage configuration is shown below:

Figure Modbus Polling Web Page Configuration Screenshot
(2) AT commands setting: Enable or disable the Modbus polling feature, and enable the Modbus polling function. AT+MODBPOLLEN=on/off Set the polling interval for querying (50~65535) milliseconds, using 200ms as an example. AT+MODBPOLLT=200
6.15 KEEPALIVE FUNCTION With the addition of a Keepalive mechanism during TCP connections, RS232/485 TO WIFI ETH (B)
can promptly detect network anomalies and disconnect when there’s a network issue. Once the network is restored, it can swiftly reconnect to the server.
6.16 WEBSOCKET FUNCTION This WIFI serial server can realize the function of websocketserver. It can make the serial port of
WIFI serial server interact with the web page in real time, instead of the earlier HTTPGET, POST and PUT modes, and the response speed is faster. This WIFI serial server provides a corresponding websocket test page for users to test, and the specific page is as follows: (The address of this page is 10.10.100.254/websocket.html).
6.17 MQTT FUNCTION

6.17.1 MQTT FUNCTION INTRODUCTION

MQTT is a protocol for message publishing//subscribe transmission based on the client servers. The MQTT protocol is lightweight, simple, open, and easy to implement, which makes it highly versatile and applicable in a wide range of scenarios. The MQTT function settings of RS232/485 TO WIFI ETH (B) are highly flexible, allowing you to configure almost all MQTT protocol-related connection parameters, publish topic parameters, and subscribe topic parameters. RS232/485 TO WIFI ETH (B) MQTT’s publish topic modes include Pure Transparent Publish Mode (serial port can transparently publish data to all topics), Special Identifier Publish Mode (serial port can transparently publish data to specific topics using identifiers), and Custom Topic Publish Mode (serial port can transparently publish data to specified topics).

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RS232/485 TO WIFI ETH (B) MQTT’s subscribe topic modes include Pure Transparent Subscribe Mode (subscribed topic data transparently transmitted to the serial port) and Topic-Carrying Subscribe Mode (subscribed topic data carrying the topic is transparently transmitted to the serial port).

6.17.2 RS232/485 TO WIFI ETH (B) PARAMETER CONFIGURATION The AT command settings are as follows in the table below:
Table MQTT-related commands

Command MQTTEN MQTTVER MQTTSVR MQTTID MQTTUSR MQTTPWD MQTTHEART MQTTWILLEN MQTTWILL MQTTLINK MQTTPUBMOD MQTTPUBLS MQTTPUBADD MQTTPUBDEL
MQTTPUBCLR MQTTSUBMOD MQTTSUBLS MQTTSUBADD MQTTSUBDEL
MQTTSUBCLR

Note Turn MQTT function on/off Query/set MQTT version number Query/set MQTT server information Query/set MQTT client ID Query/set MQTT authentication user name Query/set MQTT authentication password Query/set MQTT heartbeat interval Query/set MQTT last will status Query/Set the MQTT last will message. Query the MQTT connection status. Query/Set the MQTT topic publishing mode. Query the list of preconfigured MQTT publish topics. Add a new topic to the preconfigured publish topics. Delete the topic with that name from the preconfigured publish topics. Clear the preconfigured publish topics. Query/Set MQTT Topic Subscription Mode Query MQTT preconfigured subscription topic list Add a new topic to a preconfigured subscription topic Delete a topic with that name from the preconfigured subscription topics. Clean preconfigured subscription topics

Web page settings On the “MQTT Function Settings” page, configure the MQTT function parameters as follows:

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RS232/485 TO WIFI ETH (B) User Manual

Figure MQTT function settings page

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References

• Waveshare Electronics
• pico.wiki/esp-chart.php

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