Overview
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Schematics Illustrated PartsInstallation
Cine Bridge PCB
The main purpose of the Cine Bridge PCB is to generate another PCI bus (PCI Bus 1) that is separate but linked to the
Host Pentium CPU’s PCI Bus (PCI Bus 0). Although the Host Pentium CPU maintains control of PCI Bus 1, it is
actually a reserved, high-capacity data path between frame memory on the Cine Bridge PCB and the Cine Disk array.
Having a separate PCI bus enables the Host Pentium CPU to maintain its full PCI bandwidth while images transfer at
required speed to and from the Cine Disk drives.
The Cine Bridge PCB accepts X-Ray image data from the Image Processor as 10-bits-per-pixel parallel data. During
image acquire mode, the Cine Bridge PCB packs three pixels into a single 32-bit word and stores the packed image in
one of three frame buffers. During image playback, frame data from the disk drives fill one buffer while a pixel packer
unpacks a different buffer. The Cine Bridge PCB returns image data to the Image Processor in the 10-bit-per-pixel
parallel format.
Cine Disk Array Controller
The cine disk array controller is also known as the Fibre Channel Arbitrated Loop (FC-AL) Disk Controller. It provides
the data interface between the Cine Bridge PCB and the cine disk drives. The controller’s job is to exchange image
data with the frame buffers on the Cine Bridge PCB and the Cine Disk drives.
The FC-AL serial data loop daisy-chains to each drive, starting at the controller and returning there after passing
through the backplanes. Loop data leaves the controller on fibre channel cable and arrives at the Two-Disk
Backplane, where it enters the first disk drive and then the second disk drive on the backplane. The output of the Two-
Disk Backplane feeds the input of the Four-Disk Backplane, again on fibre channel cable. After passing serially
through each drive on the Four-Disk Backplane, the 1.063 Gb/s loop data returns to the controller, once more on fibre
channel cable.
CAUTION: Fibre channel cable is very fragile. If the foam core supporting either conductor is kinked or pinched,
an impedance “bump” occurs at that point, attenuating the high rate FC-AL signal and sometimes
causing data loss. Never compress a fibre channel cable or bend it with a radius of less than 0.5
inches.
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