MTP3SendData

Requests data to be transmitted to a specified signaling point.

Prototype

DWORD NMSAPI MTP3SendData ( CTAHD ctahd, S16 sapId, U32 opc, U32 dpc, U8 lnkSel, U8 priority, U8 *data, S16 length, U8 srvInfo)

Argument

Description

ctahd

Natural Access handle.

sapId

Service access point ID. Specify the same value used for ctaOpenServices.

opc

24-bit, 14-bit, or 16-bit originating point code to be inserted in the outgoing message.

dpc

24-bit, 14-bit, or 16-bit destination point code of the remote system.

lnkSel

Link selector used by MTP 3 to choose the link to send data over. Valid ranges are 0 through 15 for ITU-T and 0 through 31 for ANSI.

priority

Priority of the message. Valid range is 0 (lowest) through 3 (highest).

data

Pointer to the address of a buffer of data to transmit.

length

Length (in octets) of the data in the data field.

srvInfo

Service information octet (SIO) in which the application is interested.


Return values

Return value

Description

MTP3_SUCCESS

 

MTP3_INVBOARD

Invalid board number.

MTP3_NOT_BOUND

ctaOpenServices not previously called.

MTP3_OSERROR

Lower-level drivers or task returned an error.

MTP3_RESOURCE

Host running out of buffers to send to the board. See the Details section for more information.


Details

Both opc and dpc are passed as 32-bit values. For example, the 24-bit point code 5.49.7 is passed as 0x053107.

For TUP only, all 8 bits are available to the application with no lnkSel range checking. For more information, refer to Outbound messages.

The user data sent is unique. The first byte corresponds to the first byte following the routing label in the underlying SS7 data message. For example, when constructing an ISUP message, the first byte of user data is the first byte of the circuit identification code (CIC). The MTP layer 3 constructs the routing label and SIO values from other parameters and bind information. The user application is responsible for any byte-order translation necessary for all data in the data field.

The SIO must be unique for each application. The service information field is composed of service indicator and network indicator fields. Only the service indicator field is used for routing of incoming messages.

If you receive an MTP3_RESOURCE error, perform one or more of the following tasks:

For more information, see Transferring data.