GPRS Modems FAQ

1. GPRS Modules Settings

  • check whether the serial parameters of working parameters and the GPRS modules of GPRS modems agreement
  • serial line, check whether it is normal
  • check the line connection is normal
  • check using the serial line sequence, TXD to RXD, RXD to TXD, GND to GND
  • check whether electricity module, check module power supply is normal, the default for 12V power supply

2. AT commands to send and return instruction

A.if you can read the normal setting and parameter, instruction transmission and return is normal
B.transparent transmission mode using the AT instruction, need to send + + + returns a, then sends the a within 3s, return to the +ok, that can normally enter the AT command mode

3. Network Connections

A.no network connection

  • Check whether it has been to the GPRS modules electricity (POW lights, NET lights flash)
  • Check before switching on the power, whether the inserted SIM card
  • The examination of whether the SIM card arrears, whether open flow
  • Check that there is no connection of antenna
  • Check whether the user to set the target IP and port can be connected through the public network;
  • Check whether the user to set the target domain name and port can be connected through the internet;
  • Check the firewall, antivirus software, such as whether to disable the server software network function

B.easily Network drop

  • Check whether the connection of antenna, check the server and network environment is normal and stable
  • Check the user network environment, port forwarding to the computer, doing port forwarding computer IP address needs to be a static IP, avoid the unknown error cause routing redistribution after IP

4. communication and data transmission

A.computer testing communication is not normal: check the serial port settings parameters.

B.Computer test OK, GPRS Modmes connection cannot be serial communication equipment. Check the connection line connecting device: for the use of serial cross line or serial port to connect directly, because the user equipmentdiffer in thousands of ways, connection mode, the TXD is connected to RXD, RXD is connected to TXD; GND is connected to the GND, the interface definition of GPRS Modmes 232 interface: DB9-F pin2-TXD, pin3-RXD, 5-GND, does not support flow control

C.Check GPRS modems equipment serial port parameters and whether the serial port parameters matching between user equipment

D.GPRS modules communication time delay is higher, the delay demanding applications are not suitable for use, use GPRS normal within 10s delay