Prosody compact PCI installation guide
7
Aculab RJ45
'T' piece
RJ45 to BNC
adapter
RJ45 to BNC
adapte
r
Ac
ula
b card
faceplate
Port
RJ45
socket
Aculab card
Port
RJ45
socket
Port
RJ45
socket
Patch cable is not supplied by Aculab
Patch cable
WHITE = TRANSMIT
BLACK = RECEIVE
1.5
Prosody cPCI card - host interface
A device driver program, running on the host chassis, controls the operation of the Prosody cPCI
card.
The driver accesses the card via a control space within an area of shared RAM. This shared area
is a block of memory physically resident on the card that appears as a normal area of memory in
the memory map of the host chassis.
For information on device driver installation and configuration, please refer to the Aculab
publication ‘
Call, Switch and Speech Driver Installation Guide
’. This guide can be downloaded
from the Aculab company web site at
www.aculab.com
.
1.6 Call
Control
Processors on the PM4 Line Interface Module daughter-card (one processor per E1/T1 port)
control all of the call signalling (set-up, acceptance, clearing, etc.) in response to commands
from an application program running on the host computer.
The call control interface to the PM4 Line Interface Module is at a low level (in signalling terms),
and this provides maximum information and control over the various stages of call progress. This
interface is accessed via a device driver that has been prepared for the operating system in use.
The PM4 Line Interface Module processor checks each outgoing message provided by the
application program for syntax, validity of content and context. If errors are found, the call is
automatically cleared. The software on the PM4 Line Interface Module, therefore, forms an
effective barrier between the application program and the telephone network, and protects the
network from incorrect call signalling.
Several elements of call signalling related information are available to the application program,
although in some cases this depends upon provision by the Public Switched Telephone Network
(PSTN) of certain information along with each call. One such information element is the number
used by the caller on calling into the card, (the DDI number); this is only available when the
service obtained from the PSTN is of the appropriate type. Another such information element,
which may be available according to the protocol and PSTN, is Calling Line Identity (CLI),
which, on incoming calls, makes the telephone number of the calling party available to the
application program.
Full details on the control of calls using the Prosody cPCI card are available in a separate
publication ‘
Aculab Call Control API Guide
’. This guide can be downloaded from the Aculab
company web site at
www.aculab.com
