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DC 3.3V 5V CH9121 Ethernet Network Module UART to RJ45 Converter TCP/IP 100M 802.3

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  It is a UART to RJ45 Ethernet Network Converter Module with CH9121 controller.The CH9192 
has built-in TCP/IP communication protocol.It can realize two-way transparent transmission of network data packets and serial data.Support TCP CLIENT, TCP SERVER, UDP CLIENT, UDP SERVER four work method. Its maximum baud rate can be 921600bps.
  1>.Built-in MAC and PHY 
  2>.Support two-way transparent transmission
  3>.Support 10/100M
  4>.Supprot MDI/MDIX automatic conversion
  5>.Support DHCP obtain an IP address automatically
  6>.Support DNS domain name access
  8>.Support KEEP ALIVE mechanism
  9>.Supprot UART 0~2000ms timeout setting
  1>.Model: CH9121
  2>.Work Voltage:DC 3.3V~5V
  3>.UART Level: DC 3.3V~5V
  4>.Buad rate:300bps~921600bps
  5>.Work Temperature:-25℃~85℃
  6>.Work Humidity:5%~95%RH
4.Pin definition:
  1>.RESET: Input. Restore factory settings, chip power-on detection, low level is valid
  2>.RSTI: Input. External reset input,low level is valid
  3>.DIR: Output. Use control  RS485 send and receive switching
  4>.CFG: Input. Serial port configuration mode setting pin,built-in pull-up, enter the serial port configuration mode when low level is detected, high level quit configuration mode.
  5>.TCPS: Output. TCP client mode, the port is connected to the status indication pin, and the connection is successfully output low level
  6>.RXD: Input. UART data input ,connect external MCU’s TXD
  7>.RUN: Output. Module running status indication pin, output 2Hz square wave 
  8>.TXD: Output. UART data output ,connect external MCU’s TXD
  9>.GND: Power. Power ground
  10>.3V3: Power. 3.3V power supply,and 5Vpower supply pick one of two
  11>.5V: Power. 5V power supply,and 3.3Vpower supply pick one of two
5.Module configuration and working mode description:
  Module parameter configuration is divided into two parts: basic setting and port configuration, basic setting main include ,device name ,network parameter,serial port negotiation authentication function, serial port negotiation authentication function default is off status, defaulting through hardware CFG0 pin enter erial port setting mode,can through serial port negotiation enter serial port setting mode after open .CH 9121 support DHCP and manual mode two ways set the network basic parameters.
  5.1. TCP CLIENT mode 
    On the TCP CLIENT model ,after charge in the module,will take the initiative connected TCP SERVER terminal, when the connection is established, can achieve two-way transparent transmission of network data packets and serial port data , Under this mode, TCP SERVER ‘s IP need to be visible to the module,so it means via module IP can direct PING connect server IP . under TCP CLIENT mode, support local serial port random,support through domain name access remote service area, the chip internal default open TCP underlying Keep Alive mechanism,It can detect that the device is offline. TCP client Application model as below:Suitable for on-site data collection and upload server mode.
  5.2. TCP SERVER mode
    On the TCP SERVER mode,after charge in the module, Will listen to the local serial port whether have a client request connection, after the connection is established,can achieve two-way transparent transmission of network data packets and serial port data .under this mode,TCP CLIENT IP need to be visible to the module,The visible meaning is that the IP of the client can be directly ping through the client IP (see Section 4 for details). The module needs to configure network parameters there are  : working mode, device IP, subnet mask, default gateway, device port. the destination IP address, destination port, and under this mode can only support one TCP client connection at a time.
  5.3. UDP CLIENT mode
    On the UDP CLIENT mode,after charge in the module,will sent data to the local port (from the destination IP and port) transparently forwarded to the module serial port.Similarly,send to module serial port data will through UDP ways forwarded to set destination IP and port. Under this model, the module needs to configure network parameters there are : working mode, device IP, subnet mask, default gateway, device port. the destination IP address, destination port.
  5.4. UDP SERVER mode
     On the UDP SERVER mode ,received send to local IP and port all data is forwarded to the serial port, send to module serial port data also through UDP way forwarded to Communicate with UDP’s IP and serial port ,Under this model, the module needs to configure network parameters there are : working mode, device IP, subnet mask, default gateway, device port.
  1>.1pcs CH9121 Ethernet Network Module UART to RJ45 Converter 
  2>.1pcs 2.54mm 2*8Pin Male Pin
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