The Working Mode of Serial to WIFI:

Serial wireless AP (COM-AP), serial wireless STA (COM-STA) and serial wireless AP+STA (COM-AP+STA) three modes

 

The serial port WIFI module is an embedded module based on the Uart interface that conforms to the wifi wireless network standard. Built-in wireless network protocol IEEE802.11 protocol stack and TCP/IP protocol stack can realize the conversion between user serial data and wireless network. Through the serial port WIFI, the traditional serial device can also easily access the wireless network.

 

Serial wireless WIFI（COM-AP）mode, router mode. The module acts as a wireless WIFI hotspot, allowing other WIFI devices to connect to the module to implement wireless (WIFI) data conversion between the serial port and other devices. In this mode, according to the application scenario, three sub-modes can be set: TCP server, TCP client, UDP. These three sub-modes are not studied first. In short, data transmission is possible. It can be understood that the module can be as a central node. It is the creator of a wireless network and the central node of the network. The wireless router used in an ordinary home or office is an AP.

 

Serial wireless STA (COM-STA) mode, site mode. The module acts as a wireless WIFI STA (site) for connecting to a wireless network to implement wireless (WIFI) data conversion between the serial port and other devices. In this mode, according to the application scenario, three sub-modes can be set: TCP server, TCP client, UDP.  It is understood that the module can be used as access device. Each terminal connected to a wireless network (such as a laptop, PDA, and other user devices that can be networked) can be referred to as a site.

 

Serial wireless AP+STA (COM-AP+STA) mode, the module is used as both a wireless WIFI AP and a wireless STA. Other WIFI devices can be connected to the module, and the module can also be connected to other wireless networks to implement wireless (WIFI) data conversion between the serial port and other devices. In this mode, according the application scenario, nine sub-modes can be set: (TCP server, TCP client, UDP)||(TCP server, TCP client, UDP). It is understood that the module can be used as a node or as an access device.

 

TCP/IP and UDP

- TCP (Transmission Control Protocol) reliable, connection-oriented protocol (eg: make a call), low transmission efficiency, full duplex communication (transmission buffer & receive buffer), byte-oriented stream. Applications that use TCP: Web browsers; email, file transfer programs.

UDP (User Datagram Protocol) unreliable, connectionless service, high transmission efficiency (small delay before transmission), one-to-one, one-to-many, many-to-one, many-to-many, message-oriented, best service, no congestion control. Applications that use UDP: Domain Name System (DNS); video streaming; Voice over IP (VoIP).