E2054 System Description
Discrete Paging System
The
E2054 is a dedicated paging system providing a complete
commercially capable system in a 19 inch rack.
It has everything required to create
messages and send to a single transmitter or a large
multi-transmitter network.
Functionally the system is described
below;
Central
to this design is the CPU2 which operates as a dedicated
switch. It has TCP and serial port capability and the ports
are each configured to provide a particular type of service
or run a protocol to send packets through the system.
The diagram below shows the Intra-port
connectivity of CPU2 and CPU1 (E2050) and the connections to
the external environment;
CPU1 Ports B (normal paging input) and
D (priority paging input) and A (monitor port) are hardwired
to ports E, C and F on CPU2.
CPU2 Ports B and G (TCP) are the main
external communication entry points. These ports run near
identical protocols to handle the variety of packets passing
through them.
CPU2 Port D is connected to the same
port on the other E2054 system in a redundant configuration.
The connection facilitates handshake communication between
the systems for the final transmitter network.
CPU2 Port A can operate as a pure
logging input such as an off-air decoder. It also has the
ability to communicate to the B Port of the other redundant
E2054 to allow cascade operation on both systems from one
port. This means only one input is used to communicate to
both systems.
An
example of the handshake of the protocol to perform the
simple task of sending a paging message through this system is shown below.
-
Port B
is the input physical port on the E2054.
-
VC is
the virtual channel state machine in the E2054.
-
Port E is the output physical port on
the E2054 which is hardwired to Port B of the CPU1 E2050.
Redundant Paging System
The
E2054 can be configured to operate in a redundant system as
well. Both systems may operate completely separately or
together into a transmitter or network.
