Screenshots

Verify that the modem is connected and alive:

$ echo AT | atinout - /dev/ttyACM0 -
AT
OK
$

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Hang up any active calls:

$ echo ATH | atinout - /dev/ttyACM0 -
ATH
OK
$

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Add two phonebook entries:

$ atinout - /dev/ttyACM0 - <<EOF
> AT+CSCS="UTF-8"
> AT+CPBS="ME"
> AT+CPBW=,"0123456789",129,"B. Endian"
> AT+CPBW=,"8967452301",129,"L. Endian"
> EOF

OK

OK

OK

OK
$

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