Author: Barbara Schmitz, CMO MEN Mikro Elektronik
The first that comes to mind when thinking of building up hybrid systems is CompactPCI PlusIO (PICMG 2.30). Here, the system slot CPU supports both the parallel CompactPCI standard (PICMG 2.0) and the new CompactPCI Serial standard (PICMG CPCI-S.0). Hybrid backplanes from different manufacturers enable configuration with peripheral slot boards on the left and on the right of the system slot board. Up to 7 parallel and a maximum of 4 serial boards are supported - without a bridge. This way, a cost-effective migration is possible, because the usage of future-oriented and standardized data transfer based on CompactPCI Serial is guaranteed even when already integrated CompactPCI components are used.
But what if none of the standard hybrid backplanes is suitable for the new application and/or more than 4 serial peripheral boards are needed and the lot sizes are too small for the development of a customer-specific backplane (in the beginning)?
In this case, the two worlds – CompactPCI Serial und CompactPCI – have to be connected in a different way. For this, one board pair is used. One board is the interface from CompactPCI Serial to CompactPCI and is plugged into a peripheral slot of the CompactPCI Serial backplane. The second interface board replaces the system slot CPU on the CompactPCI backplane and is connected to the first interface board via a cable at the front panel. The new system slot board in the CompactPCI system is equipped with a PCI Express to PCI bridge, the communication over the cable is based on a PCI Express x1 link. As both standards are compatible to the 19" mechanics, the solution can be accommodated in one rack. On the other hand PCI Express enables cable lengths of up to 7 m so that two racks can also be coupled loosely.
If - for larger volumes - the development of a customer-specific backplane is profitable, the PCI-Express-based connection of CompactPCI Serial to CompactPCI can be done via rear I/O. This means that only the second interface board is needed which is plugged into the system slot of the CompactPCI side.
This example shows once again how consequently CompactPCI Serial follows up on its parallel predecessor. CompactPCI Serial makes modern technology simple, robust, flexible and inexpensive - while the mechanics remain 100% compatible with CompactPCI 2.0.