Dual PCI-bus designs support high-speed data-transfer rates
Cameras that operate at data-transfer rates of 100, 120, or 200 Mbyte/s and faster generally swamp the maximum bandwidth of the PCI bus. Accordingly, systems integrators are looking at dual PCI-based motherboards to house multi-frame-grabber configurations. By partitioning the high bandwidth of such cameras between two on-board PCI buses and frame grabbers, systems integrators can achieve up to 200-Mbyte/s data-transfer rates.
At Photonics West (Jan. 1999; San Jose, CA), BitFlow Inc. (Woburn, MA) demonstrated such a system using two cameras from Dalsa Inc. (Waterloo, Ontario, Canada). Each camera delivered 100-Mbyte/s image data to system memory via two BitFlow RoadRunner digital camera interface boards (see Vision Systems Design, April 1999, p. 9). At the International Robots & Vision Show (May 1999; Detroit, MI) Epix Inc. (Buffalo Grove, IL) demonstrated a similar system using its Pixci D32 PCI-based frame grabber.
"As a PCI imaging board for digital-output cameras, the single-board Pixci 32 provides an interface for up to four digital outputs, or 32 total data bits, at the maximum sustained data-transfer rate of the PCI bus, approximately 105 Mbyte/s," says A. C. Petersen, president of Epix. Therefore, a single Pixci board can be used in a number of different configurations.
For the Dalsa MotionVision and Piranha cameras, which have four 8-bit outputs that operate at 25 MHz and result in a data stream of 100 Mbyte/s, a single frame grabber is required. For cameras such as the Megaplus 1.0 1215 from Eastman Kodak, Motion Analysis Systems Division (San Diego, CA), that output 48 bits at a resolution of 1k x 1k and a data rate of 15 frames/s, using two Pixci D32 imaging boards on a single PCI bus provides an interface for up to 64 data bits.
"Some cameras, such as the Dalsa CT-F3-4096W time-delay-integration (TDI) camera, the Kodak Megaplus ES1.0/1260 area-scan camera, and the Silicon Mountain Design (Colorado Springs, CO) 4M 15-20 area-scan camera, provide up to 200-Mbyte/s data-transfer rates. The Dalsa TDI camera, for example, transfers 4096 pixels at 44 kHz and results in a 200-Mbytes/s transfer rate," says Epix`s Petersen. To interface to this camera, a dual-PCI-bus computer, such as the L440 Pentium-based motherboard from Intel Corp. (Santa Clara, CA), can be used with two Pixci D32 boards.
