How to call short numbers (like 911) on gsm module via AT Command

Question

I use Telit GL865 Module, call to short numbers services. For instance 911, 112, 7000 etc services numbers. I can call some telephone form my gsm module via this AT command;

ATD+<NUMBER>;

example: ATD+15552224455;

But ATD+911; or ATD+7000 not working. I also tried to add country code at the starting side like,

ATD+1911 (for america) it didnt work.

So how can I do that?

Answer 1

ATD112; works. sim features are important. mine's is vodafone 64kb.

Answer 2

The complete list of emergency numbers is a bit tricky because that it is dependent on (varying) content on the SIM card (EF_ECC).

11.14 says under 6.4.13 SET UP CALL

It is possible for the SIM to request the ME to set up an emergency call by supplying the number "112" as called party number. If the SIM supplies a number stored in EF_ECC, this shall not result in an emergency call.

22.101 says under 10 Emergency Calls

Emergency calls shall be supported by the UE without a SIM/USIM/ISIM being present. ... The Home Environment operator shall specify preferred emergency call numbers (e.g. 999 for UK citizens or 110, 118 and 119 for Japanese citizens). These emergency call numbers shall be stored in the SIM/USIM and the ME shall read this and use any entry of these digits to set up an emergency call. It shall be possible to store more than one instance of this field.

and under 10.1.1 Identification of emergency numbers

The ME shall identify an emergency number dialled by the end user as a valid emergency number and initiate emergency call establishment if it occurs under one or more of the following conditions. If it occurs outside of the following conditions, the ME should not initiate emergency call establishment but normal call establishment. Emergency number identification takes place before and takes precedence over any other (e.g. supplementary service related) number analysis.

a) 112 and 911 shall always be available. These numbers shall be stored on the ME.

b) Any emergency call number stored on a SIM/USIM when the SIM/USIM is present.

c) 000, 08, 110, 999, 118 and 119 when a SIM/USIM is not present. These numbers shall be stored on the ME.

d) Additional emergency call numbers that may have been downloaded by the serving network when the SIM/USIM is present.

So in your case, I think 112 should be the safest bet. You could perhaps try to read and parse EF_ECC with AT+CRSM but that is seriously hairy low level SIM stuff...