Initiate an SBD Session Extended

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The +SBDIX command must be used in place of the +SBDI command for applications wishing to make use of SBD Ring Alert functionality

Command format:

+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)

mmm

Thousandths of minutes longitude (000-999)

The optional sign indicators specify latitude North (+) or South (-), and longitude East (+) or West (-). If omitted, the default is +.

For example:

AT+SBDIX=5212.483,-00007.350

corresponds to 52 degrees 12.483 minutes North, 0 degrees 7.35 minutes West.

Command Response

+SBDIX:<MO status>,<MOMSN>,<MT status>,<MTMSN>,<MT length>,<MT queued>

where:

<MO status>:

MO session status provides an indication of the disposition of the mobile originated transaction. The field can take on the following values:

0

MO message, if any, transferred successfully.

1

MO message, if any, transferred successfully, but the MT message in the queue was too big to be transferred.

2

MO message, if any, transferred successfully, but the requested Location Update was not accepted.

3 .. 4

Reserved, but indicate MO session success if used.

5 .. 8

Reserved, but indicate MO session failure if used.

10

GSS reported that the call did not complete in the allowed time.

11

MO message queue at the GSS is full.

12

MO message has too many segments.

13

GSS reported that the session did not complete.

14

Invalid segment size.

15

Access is denied.

16

ISU has been locked and may not make SBD calls (see +CULK command).

17

Gateway not responding (local session timeout).

18

Connection lost (RF drop).

19

Link failure (A protocol error caused termination of the call).

20 .. 31

Reserved, but indicate failure if used.

32

No network service, unable to initiate call.

33

Antenna fault, unable to initiate call.

34

Radio is disabled, unable to initiate call (see *Rn command).

35

ISU is busy, unable to initiate call.

36

Try later, must wait 3 minutes since last registration.

37

SBD service is temporarily disabled.

38

Try later, traffic management period (see +SBDLOE command)

39 .. 63

Reserved, but indicate failure if used.

64

Band violation (attempt to transmit outside permitted frequency band).

65

PLL lock failure; hardware error during attempted transmit.

<MOMSN> :
The Mobile Originated Message Sequence Number (MOMSN) is a value assigned by the ISU when sending a mobile-originated message to the GSS. This value is incremented each time an SBD session is successfully completed between the ISU to the GSS. This wrap around counter can range from 0 to 65535.

<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.