The benefits of migration to PICMG 1.3 for embedded computing applications
By Jack Chang and Bruce Tsai, ADLINK Technology Inc.
The standards based system/peripheral card-on-backplane architecture is well accepted in the embedded computing industry. The first industry standard for system/peripheral card-on-backplane was PICMG 1.0, which supports a PCI/ISA interface from board to backplane. The establishment of this standard provided a stable and efficient environment for manufacturers to simplify design efforts, minimize costs, allow interoperability of products from different vendors, and stimulate new product development. The main advantages of the card-on-backplane architecture are faster Mean Time To Repair (MTTR) over conventional motherboard designs, flexible backplane slot configurations, and the ability to use a broad range of off-the-shelf peripheral cards.
The PICMG 1.3 specification is the latest evolution in PICMG 1.x system designs, and addresses the need for faster system platforms with high bandwidth interfaces to peripheral cards. Flexible system design and PCI/PCI-X compatibility of the older specifications have been preserved with PICMG 1.3, but the ISA bus has been replaced by point-to-point PCI Express serial links, advanced features such as IPMI, Serial ATA, USB, and Ethernet connections, and additional power pins via the edge connectors. The PICMG 1.3 specification allows users to take maximum advantage of the latest chipset functionalities, provides increased bandwidth capability, and allows flexible and simplified system design.
Figure 1: PICMG 1.3 Full-size SHB dimensions and connector locations
Advantages of PICMG 1.3
The PICMG 1.3 specification provides several advantages over PICMG 1.0. The ability to support PCI Express point-to-point serial links to the backplane overcomes the data bottleneck of PCI and ISA parallel busses. PICMG 1.3 replaces the PCI/ISA bus combination with PCI Express, allowing the use of the latest high performance peripheral cards, including PCI Express x16 graphics cards, and retains PCI(-X) support for legacy devices. The increase in available bandwidth with PICMG 1.3 is summarized in Table 1 below.
Table 1: Increase in available bandwidth with PICMG 1.3
By enabling all power to be delivered by the edge connectors and offering optional I/O connections to the backplane (SATA, USB, LAN, IPMB, SMBUS, and power signals), auxiliary power connectors can be eliminated and chassis cabling significantly reduced, simplifying system design, improving internal airflow for better thermal performance, and decreasing MTTR. In particular, SATA, USB, and LAN I/O signals can be routed to desired locations on the backplane to suit the user's specific application (e.g. close to the front or rear of the chassis). Remote system management and monitoring supported by the optional IPMB provides an additional advantage over PICMG 1.0 systems.
The PICMG 1.3 specification utilizes the full functionality of the latest CPUs and chipsets, an example being ADLINK's NuPRO-E320 full-size SHB, supporting the Intel's Core™2 Quad processor and Q45 Express Chipset. Various backplane configuration options are provided by the PICMG 1.3 specification to meet the different needs encountered in embedded computing applications. Figure 2 shows an example of a PICMG 1.3 backplane, the ADLINK EBP-13E4, which takes advantage of the key features of the NuPRO-E320, providing a PCIe x16 slot, 3 PCIe x4 slots, 7 PCI slots, 2 SATA connectors, and 4 USB ports by pin header.
The latest PICMG 1.3 SHBs provide more computing power and higher memory capacity for complex image processing. Additionally, the improved performance, bandwidth and flexibility provided by PICMG 1.3 make the architecture ideal for tasks requiring high-speed data transfer such as automated optical inspection (AOI) and other digital imaging applications with ever-increasing performance demands.
An example of a PICMG 1.3 machine vision solution could include the SHB/backplane combination shown in Figure 2 above, combined with ADLINK's PCIe-FIW64 PCI Express frame grabber card, PCI-8164 motion control card, and a suitable 1394b camera. For video surveillance applications using standard cameras, ADLINK's PCIe-RTV24 real-time video capture card provides image acquisition performance required by today's security needs.
The PICMG 1.3 specification brings an improved level of PCI Express functionality and performance to embedded computing platforms and continues support of PCI(-X) cards, while maximizing system design flexibility. Power and I/O options reduce system development and implementation costs and further decrease MTTR over that of PICMG 1.0. The combined features of the PICMG 1.3 specification allow a cost-effective migration from PICMG 1.0 or traditional motherboard-based system to an improved modular embedded platform supporting the latest in processor/chipset performance and PCI Express technology.