GSM modem returning what I send via USART terminal

Question

I am using at command to control a USB modem. When I send a command to this modem I receive some data including the command I send. Example:

AT

OK

AT+CUSD=1,"*778#",15

OK

+CUSD: 0,"Balance: 7.50 TK. Validity: 02-Sep-13. Bonus: 0.00TK. Free Min: 0.",64

But what I want is like this:

OK

OK

+CUSD: 0,"Balance: 7.50 TK. Validity: 02-Sep-13. Bonus: 0.00TK. Free Min: 0.",64

Is there any at command available that can prevent this modem to show sending command again.

Answer 1

According to this Wikipedia article on the Hayes command set used by modems, there are two commands that control the echoing behavior of the modems:

• E0 turns the echoing off, so the modem will not repeat the command that was sent to it
• E1 turns echoing back on

What you are looking for is the E0 or the E command, where the latter is only a shorthand for the first one.