Siemens M20 Terminal Technical Description page 57

Siemens Information and Communication Products
AT+CAMM Accumulated call meter maximum (ACMmax) set or query
Test command Response
AT+CAMM=? OK
Parameter
Read command Response
AT+CAMM? TA returns the current ACMmax value.
+CAMM: <acmmax> OK
If error is related to ME functionality:
+CME ERROR: <err>
Parameter
see set command
Set command Response
AT+CAMM=[<ac TA sets the Advice of Charge related to the accumulated call meter maximum value in SIM file EF
mmax>[,<pass- (ACMmax). ACMmax contains the maximum number of home units allowed to be consumed by
wd>]] the subscriber.
OK
If error is related to ME functionality:
+CME ERROR: <err>
Parameter
<acmmax>
<passwd>
Reference Note
GSM 07.07
Version 8 dated 15.03.00
string type; three bytes of the max. ACM value in hexadecimal format
(e.g. "00001E" indicates decimal value 30)
000000
disable ACMmax feature
000001-FFFFFF
string type
SIM PIN2
AT command interface
A
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