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L2ßeta CPU Concept
Commercial 6U CPU Card W/ UII on board
Straight pass to VME
MBUS
Cable to PMC/PCI
FPGA MBUS P I/O DMA ECL Latch Driver
Latches ECL Drivers
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Same Basic Concept as L2Alpha, but much
simplified implementation
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• Minimal engineering
• connect FPGA to MBUS,
• PCI bus to FPGA via a cable and/or driver,
• connect ECL drivers to FPGA
• This project is largely a software issue
• program FPGA
• device driver coding
• Result a clear upgrade path to modern/powerful
  CPUs and
• NO problems w/ ARCHAIC spare part hunts

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Compatibility - needs new PCI base classes
(PCIDEV, PCICFG, CIA) the UII driver should be
transparent -need new drivers for replace MB
devices and TSI - easy - minor linux
tweeks? ---gtgt result source code compatible
boards! Can select hotter CPU boards for Global
worker or cooler boards for
Administrators
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Whats on the market? Many vendors for 6U CPU
cards, most have UIIBs on board. Small
companies w/ off the shelf boards custom
options Medium companies like SBS w/ off the
shelf boards Giant companies like Raytheon
too! Medium and High End CPUs available now
vs. our alpha
SPECint95 SPECfp95
Cost Alpha 500 MHz 15.4 21.1
5K (complete) PIII
600MHZ 24 16
4K from SBS

(700 MHz price!) POWERPC
750 22.4 13.3
(550MHz) 7400 21.4
20.4 SPARC II 18
22 7K (old sparc
versions) SPARC III 35
60 !!!!!