As PCI bus technology has moved from a parallel interface to fast serial point-to-point interconnects, the popular and very successful parallel CompactPCI® specification PICMG 2.0 was significantly extended and enhanced by the newer CompactPCI® Serial standard, PICMG CPCI-S.0, in 2011. Both 3U and 6U sizes are specified, as is convection and conduction cooling. This versatility combined with the wide availability of chips, hardware, and software created for the commercial market makes CompactPCI Serial the fastest, most versatile, lowest cost modular high performance open standard for embedded computing on the market today.
With CompactPCI Serial, the CompactPCI architecture moves to serial high-speed interconnects, and more data can be transferred at higher speeds using PCI Express. Additional high speed interfaces, including Ethernet, SATA, and USB are supported.
A typical configuration of one system slot and up to eight peripheral slots does not need switches and bridges. Using the proven 19” mechanics of the IEC 1101 family, proven with CompactPCI and VME, the standard introduces a new rugged additional connector with a signal density of up to 184 pin pairs (on 3U) and transmission frequencies of 12 Gb/s. Hot Swap of boards during operation is supported, as it was with original CompactPCI.
Each system is organized as follows: a System Slot, usually the CPU and often a complete single board computer, provides 8 PCI Express links, 8 SATA/SAS, 8 USB 2.0/3.0 and 8 Ethernet interfaces plus signals for general system management and up to eight peripheral slots.
Each peripheral slot supports 1 PCI Express link, 1 SATA/SAS and 1 USB 2.0/3.0 interface. Each slot can support up to 8 Ethernet interfaces to build a full mesh interconnect without an external switch. All interfaces are accessible at the same time.
The pin assignment of the system and the peripheral slot is congruent. In this way it is possible to plug a system slot board into each peripheral slot to support symmetrical multiprocessing. This is a significant advance over other 3U/6U standards.
Star topologies are supported and each slot is given equal priority: PCI Express, SATA/SAS and USB. All peripheral slots are identical except two that are connected via PCI Express links by 8 lanes.
Ethernet is normally configured as a full mesh. Although alternate topologies are supported. Transmission is based on the proven standards for copper connections up to 10GbaseT to allow configuration of redundant, safety-critical systems. This is important for demanding mil/aero, transportation, security, and many medical applications.
CompactPCI Serial can be combined with existing CompactPCI boards by using a CompactPCI PlusIO system slot card. These hybrid systems offer an ideal migration path from parallel to serial connections.
CompactPCI Serial for Space specifically addresses the extreme environment requirements for outer space.
Revision 2, released on June 16, 2015 provides minor and incremental improvements:
- New connector, RJ6, is optional and provides an additional 48 pins of rear I/O from the System Slot. The total available I/O pins from the System Slot is now 58.
- Conduction cooling mechanicals improved (maximum handle size is now defined)
- The System Slot can now be located on the right side of the card rack as well as the left side.
- I2C management bus further defined
- Location of SATA coupling capacitors clarified
+5 and +12 volts power are normally provided by an in-rack or external power supply.
