Welltech SPCI2S Intel NetStructure SS7 Boards - Manual (Page 25)

SS7 Programmer’s Manual for SPCI2, SPCI4 and CPM8 Issue 2 Page 25
When a new call arrives the application will, in general, need to initiate two listen
commands. One command causes the resource to listen to the appropriate CT bus
channel to hear the incoming voice path and the other causes the E1/T1 interface
to listen to the output from the resource card to generate the outgoing voice path.
When a call clears, the application needs to initiate generation of the fixed idle
pattern towards the network operation (and may wish to connect an idle pattern to
the resource card).
3.4.3 Static Initialisation
Static initialisation is handled by the s7_mgt utility. For each E1/T1 line interface
unit user should include an LIU_SC_DRIVE command in the config.txt file. The
syntax for this command is detailed in appendix A.
The LIU_SC_DRIVE command has several parameters. board_id and liu_id
together uniquely identify the affected line interface unit. sc_channel is the channel
number of the first channel on the CT bus that is to be used for timeslots from the
specified LIU. ts_mask is a mask identifying which timeslots on the E1/T1 interface
are carrying voice circuits (as opposed to signalling) and therefore need to be
connected to the CT bus. The least significant bit of ts_mask should always be zero
when driving from an E1/T1 interface.
As an example consider a two board system where the first board has 4 E1 ports
and the second board has 4 T1 ports. We allow the first 512 CT bus channels to be
used by other cards in the system and therefore start at sc_channel 512.
LIU_SC_DRIVE 0 0 512 0xfffefffe * 30 E1 voice ccts on ts 1..15 & 17..31
LIU_SC_DRIVE 0 1 542 0xfffefffe * 30 E1 voice ccts on ts 1..15 & 17..31
LIU_SC_DRIVE 0 2 572 0xfffefffe * 30 E1 voice ccts on ts 1..15 & 17..31
LIU_SC_DRIVE 0 3 602 0xfffefffe * 30 E1 voice ccts on ts 1..15 & 17..31
LIU_SC_DRIVE 1 0 632 0x00fffffe * 23 T1 voice ccts on timeslots 1..23
LIU_SC_DRIVE 1 1 655 0x00fffffe * 23 T1 voice ccts on timeslots 1..23
LIU_SC_DRIVE 1 2 678 0x00fffffe * 23 T1 voice ccts on timeslots 1..23
LIU_SC_DRIVE 1 3 701 0x00fffffe * 23 T1 voice ccts on timeslots 1..23
3.4.4 Dynamic Operation
The application controls dynamic changes to CT bus switching by sending the
MVD_MSG_SC_LISTEN message to the board. This message is documented in
Section 5 of this manual. It contains the liu_id (0 .. 7), the timeslot number on the
E1 / T1 interface and the CT bus channel number (sc_channel) to which the
timeslot should listen. The message is directed to the correct board by calling the
GCT_set_instance function prior to calling GCT_send.
When a new call arrives, the application will need to instigate 2 listen commands
(although they will not necessarily both apply to the SS7 board). One will connect
the voice circuit in the forward direction and the other will connect it in the backward
direction.
When a call terminates, the application should issue a fixed data message to
ensure that the network port sees the voice idle pattern.