Specifications

ISU AT Command Reference Phase VI AT Commands
Iridium Proprietary Version 2.45
20 June 2011 83
<MT status>:
The MT status provides an indication of the disposition of the mobile terminated transaction. The field can
take on the following values:
0 No SBD message to receive from the GSS.
1 SBD message successfully received from the GSS.
2 An error occurred while attempting to perform a mailbox check or receive a message
from the GSS.
<MTMSN>:
The Mobile Terminated Message Sequence Number (MTMSN) is assigned by the GSS when forwarding a
message to the ISU. This value is indeterminate if the field <MT status> is zero. This wrap around
counter can range from 0 to 65535.
<MT length>:
The MT length is the length in bytes of the mobile terminated SBD message received from the GSS. If no
message was received, this field will be zero.
<MT queued>:
MT queued is a count of mobile terminated SBD messages waiting at the GSS to be transferred to the ISU.
10.14 +SBDIX[A] - Short Burst Data: Initiate an SBD Session Extended
Note: The +SBDIX command must be used in place of the +SBDI command for FAs wishing to make use
of SBD Ring Alert functionality.
Exec Command: +SBDIX[A][=<location>]
This command initiates an SBD session between the ISU and the GSS, setting the SBD Session Type
according to the type of command +SBDIX or +SBDIXA, Delivery Short Code according to the value
specified by the +SBDDSC command, and the type of location according to whether the optional location
value is provided. If there is a message in the mobile originated buffer it will be transferred to the GSS.
Similarly if there is one or more messages queued at the GSS the oldest will be transferred to the ISU and
placed into the mobile terminated buffer.
 The message, if any, in the mobile originated buffer will be sent from the ISU to the GSS.
 If there is a message queued at the GSS it will be transferred to the ISU and placed into the
mobile terminated buffer.
 This command will always attempt an SBD registration, consisting of attach and location
update, during the SBD session in order to support SBD Ring Alert. If this is not desired, the
+SBDI command should be used.
 The FA should append an ‘A’ to the command, i.e. +SBDIXA, when the SBD session is in
response to an SBD ring alert.
<location> has format:
[+|-]DDMM.MMM,[+|-]dddmm.mmm
where:
DD Degrees latitude (00-89)
MM Minutes latitude (00-59)
MMM Thousandths of minutes latitude (000-999)
ddd Degrees longitude (000-179)
mm Minutes longitude (00-59)