Motorola g20 Developer's Manual page 310

Using the Commands
Example
1. Send at+cmux=0
2. Open DLC0 , DLC1 , DLC2, in this order
3. Open GPRS session or CSD on DLC1
4. Send AT+CSQ on DLC2
5. Send/Receive SMS on DLC2
6. Open GPRS session or CSD on DLC1
7. AT+CNMI=,1
8. AT+CMGL
9. AT+CMSS=1,"my phone num"
296 98-08901C68-O