at cmd back

AT command is tool to control modem of feature phone or smart phone. Use minicom in ubuntu.

cmd

Using minicom or sudo minicom to make communication.

$ minicom minicom: cannot open /dev/ttyACM0: No such file or directory

$ sudo minicom [sudo] password for: minicom: cannot open /dev/ttyACM0: No such file or directory

fail reason

need to enable ATCI port.

solution

  1. open engineer mode in dialer (##….)
  2. Log and Debugging
  3. ATCI
  4. (Disable ATCI) – Always enable ATCI/Enable ATCI Once (this will open Others – USB ACM – Close port/Open GS0 port) ctrl + a — z — e : OPEN echo your input when you key something on the screen

AT cmd list

AT+EPBSE?
+EPBSE: <gsm_band>,<umts_band>,<lte_band_1_32>, <lte_band_33_64>
Set: AT+EPBSE=<gsm_band>,<umts_band>,<lte_band_1_32>,<lte_band_33_64>

get current highlight band

at+epbse=?
2G  3G  LTE1-32 LTE33-64
+EPBSE: 154,145,20,128
OK

get current enabled hightlight band

at+epbse?
+EPBSE: 154,145,20,128
OK

when you uncheck the first 3G band (WCDMA-IMT-2000) manually in the engineer mode

at+epbse?
+EPBSE: 154,144,20,128
OK

==> 145 change to 144

uncheck some bands by send AT cmd, remove EGSM900

at+epbse=152
OK

if you want change 3g band, need add 2g first

at+epbse=145
+CME ERROR: 100
at+epbse=154,145
OK
at+epbse=152,144
OK
at+epbse=154,145,4,0
OK
at+epbse=?
+EPBSE: 154,145,20,128
OK

NEED RE-enter current page, and not impact SIM2?!

bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0 1 0 0 0 0 0 0 0 40 39 38 37 36 35 34 33

at+epbse=?
+EPBSE: 154,145,134217941,0
OK
at+epbse=?
+EPBSE: 154,147,524501,0
OK

erat

at+erat=?
+ERAT: (0-7, 11, 14)
OK
at+erat?
+ERAT: 0,0,6,4
OK