HF2111 GPRS Serial Server User Manual
Shanghai High-Flying Electronics Technology Co., Ltd
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Function
Name
Description
communicate)
RS422/RS485
RS422/RS485 Interface
SIM Card
Sim Card Slot
DC Input
DCPower 5~36V Input
Earth
Connect to Protect GND
Antenna
SMA Antenna Interface
LED
Indicator
Power
3.3V Internal Power Supply Indicator
NET
On: Socket TCP connect to server
success
Off: No Socket TCP connection
Active
Data receive Indicator
Flash When receive UART data.
Button
Reset
Click to restore to factory setting
Switch
Protect/Reload
Reserved, switch to H by default
1.2.2. RS232 Interface
Device serial port is male(needle), RS232 voltage level(can connect to PC directly), Pin
Order is cosistent with PC COM port. Use cross Cable connected with PC(2-3 cross, 7-8
cross, 5-5 direct), see the following table for pin defination.
Figure 2.
RS232 Pin Defination(Male/Needle Type)
Table3.
RS232 Interface
Pin Number Name
Description
2
RXD
Receive Data
3
TXD
Send Data
5
GND
GND
7
RTS
Request to Send
8
CTS
Clear to Send
1.2.3. RS485 Interface
RS485 use two wire links, A(DATA+), B(DATA-). Connect A(+) to A(+), B(-) to B(-) for
communication.
The RS485 interface support maximum 32 485 device, special hardware version can
support max 255 device. The cable maximum length is 1200 meters. Need to add
120Ohm terminal resistor for over 300 meters.
1.2.4. RS422 Interface
RS422 interface use T+/T-/R+/R-, cross connect to device as the following picture.