A9 Thinker network garbage text

[grahamg1904]

I am new to GSM and getting my head around the AT commands.

All goes at 115,200 baud with AT+GMR and AT+CMGF and AT+CMGS for SMS etc but when I ask the network provider using the USSD structure i get total garbage in the response:

AT+CUSD=1
OK
AT+CUSD=1,"123888#",15<C/R> //ask for own number
CUSD: 2,"... all garbage here", 15

Also with the "balance" of the SIM card.

I have changed AT+CSCS="GSM" but the result is same.

Has anyone anyone an idea.?

Graham
(getting older by the hour and growing grey hairs)

[pert]

I moved your topic to an appropriate forum category @grahamg1904.

In the future, please take some time to pick the forum category that best suits the subject of your topic. There is an "About the _____ category" topic at the top of each category that explains its purpose.

This is an important part of responsible forum usage, as explained in the "How to get the best out of this forum" guide. The guide contains a lot of other useful information. Please read it.

Thanks in advance for your cooperation.

[horace]

how are you powering the modem? the modem can pull 2 or 3 amps when transmitting
you usually require an external power supply

[grahamg1904]

A good idea. Thank you for your input....

Currently uses an external power supply but it would not respond like this:

+CUSD: 2, "Ù2›ý²ïºÔœ&§D'(=aÉn·î6»Ñf7" ,15

Result of an incoming of an SMS works 100%

[horace]

what is the host microcontroller?
how is it connected? what baudrate are you using?
can you post your code? select < CODE/ > and paste text where it says “type or paste code here”

[grahamg1904]

The "host" is the A9 Thinker and the data input is a laptop using the USB to UART interface and the standard AT commands as is of GSM 07.05 standard. Using Arduino IDE and the serial monitor is the same.

Sending an SMS using AT+CMGS etc. is received 100% at the sending number like vice versa receiving SMS, it is the network responses that is the problem as it seems a language reply problem.