问题
I want to check balance of sim card via AT command . Everything is running fine. But i am not able to enter in menu of response. When i am trying to enter in it Its giving me "invalid request" error from operator. While in mobile phone its working fine.
Checking Selected Port COM11
Data Received - AT+CNMI=1,1
AT
OK
OK
Data Received - AT+CUSD=1,*121#
OK
Data Received -
+CUSD: 2,"My Airtel App:Track your daily data usage, balance, validity and
Recharge online. Download now from Play Store/ App Store",15
Data Received -
+CUSD: 1,"919771272794
1 Change Language
2 Balance
3 New Offers
4 My Offer
5 My Account Info
6 Coupon Recharge
7 Other Services
8 DTH
9 Payments Bank
",15
Data Received - > AT+CUSD=1,2
OK
Data Received -
+CUSD: 1,"Invalid request.
1 Change Language
2 Balance
3 New Offers
4 My Offer
5 My Account Info
6 Coupon Recharge
7 Other Services
8 DTH
9 Payments Bank
",15
回答1:
First use **
AT+CSCS="GSM"
AT+CUSD=1,"*121#",15
**
And you'll get the following message (as usual)
*CUSD: 1,"My Airtel App:Track your daily data usage, balance, validity and
Recharge online. Download now from Play Store/ App Store",15
Data Received -
+CUSD: 1,"919771272794
1 Change Language
2 Balance
3 New Offers
4 My Offer
5 My Account Info
6 Coupon Recharge
7 Other Services
8 DTH
9 Payments Bank
",15*
Now
AT+CUSD=1,"n",15
n is your choice number. eg: to get the balance you will enter
AT+CUSD=1,"2",15
I had the same problem.
来源：https://stackoverflow.com/questions/49467914/issue-with-atcusd-command