Telecommunication apparatus

1. A rear panel transition module having a standard compact Peripheral Component interconnect (cPCI) input/output (I/O) bus interface coupled to a standard J1 connector for connection to a rear side of a backplane having a cPCI bus connector conforming to the cPCI bus standard, the rear panel transition module further comprising:

an external connector having an input for receiving input signals,

an interface circuit coupled to the external connector;

at least one processing unit coupled between the interface circuit and the standard cPCI I/O bus interface; and

an interrupt assignment link for optionally coupling one of four interrupt lines from the cPCI bus connector to an interrupt signal on the rear panel transition module.

2. A rear panel transition module according to claim 1 , further comprising a controller to support live insert functionality (hot-swap).

3. A rear panel transition module according to claim 1 , wherein the external connector is any one of BNC, D-type or SC/FC.

4. A rear panel transition module according to claim 1 , wherein the at least one processing unit performs initial filtering and/or processing of a signal input.

5. A transition module having an input/output (I/O) bus interface coupled to a connector for connection to a backplane having a bus connector, the transition module further comprising:

an external connector having an input for receiving input signals;

an interface circuit coupled to the external connector;

at least one processing unit coupled between the interface circuit and the I/O bus interface; and

an interrupt assignment link for optionally coupling one of four interrupt lines from the cPCI bus connector to an interrupt signal on the rear panel transition module.

6. A modularised card apparatus a backplane having a rear side and a front side and conforming to the cPCI bus standard, the backplane having a cPCI bus connector, the modularised card apparatus comprising:

a front processing card having a processing unit and a first cPCI input/output (I/O) bus interface for connecting to a slot on the front side of the backplane; and

a rear transition module having:

a second cPCI I/O bus interface coupled to a standard J1 connector for connecting to a rear slot on the rear side of the backplane;

an external connector having an input for receiving input signals;

an interface circuit coupled to the external connector;

at least one processing unit coupled between the interface circuit and the second cPCI I/O bus interface; and

an interrupt assignment link for optionally coupling one of four interrupt lines from the cPCI bus connector to an interrupt signal on the rear panel transition module.

7. A modularised card apparatus according to claim 6 wherein the front processing card has no external connection provided thereon.

8. A modularised card apparatus according to claim 6 , wherein the cPCI bus connector on the backplane is a feed-through connector.

9. A modularised card apparatus according to claim 8 wherein the rear transition module further comprises a resistive electrical connection between an IDSEL input on the second cPCI I/O bus interface and an appropriate address line.

10. A modularised card apparatus according to claim 8 , wherein a resistive electrical connection is provided on the rear transition module between an INTA# pin on the second cPCI I/O bus interface and an INTD# pin on the rear side of the backplane.

11. A modularised card apparatus according to claim 6 , wherein the backplane comprises a plurality of slots on the rear side.

12. A modularised card apparatus according to claim 11 wherein an IDSEL input on the second cPCI I/O bus interface is connected to an appropriate address line via a resistive electrical connection provided on the backplane.

13. A modularised card apparatus according to claim 12 wherein the IDSEL pin on the first cPCI I/O bus interface is connected to a ground plane.

14. A modularised card apparatus comprising:

a backplane having a first side and a second side, the backplane having a bus connector;

a processing card having a processing unit and a first input/output (I/O) bus interface for connecting to a slot on the second side of the backplane; and

a transition module having a second I/O bus interface coupled to a connector for connecting to a slot on the first side of the backplane, the transition module including:

an external connector having an input for receiving input signals;

an interface circuit coupled to the external connector;

at least one processing unit coupled between the interface circuit and the second I/O bus interface; and

an interrupt assignment link for optionally coupling one of four interrupt lines from the cPCI connector to an interrupt signal on the rear panel transition module.