Common Modem AT Command Strings

Error Correction Commands

 

Error correction helps cut down on noise and other phone line problems, which will result in less data loss. The packet design of error correction can also lead to greater throughput.

 

Despite the benefits, in some cases, it is necessary to disable error correction. Connecting to an old 2400 modem, which cannot perform error correction, would be one such case.

 

To disable error correction:

  • For US Robotics Modems, use the command AT&M0
  • For Rockwell Modems, use the command AT\N0
  • For Hayes Modems, use the command &Q6

 

Data Compression Commands

 

Besides error control protocols, all current high-speed modems also support data compression protocols. That means the sending modem will compress the data on-the-fly and the receiving modem will decompress the data to its original form.

 

In some cases, it is necessary to disable data compression.

 

  • For US Robotics Modems, use the command &K0
  • For Rockwell Modems, use the command %C0
  • For Hayes Modems, use the command ATS110=0