Mitsubishi Apricot FT2200, Системное руководство

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System Introduction 1-5
Orion PCI Bridge
The Orion PCI bridge (OPB) is a low-cost I/O subsystem solution for
high-performance systems. The OPB translates transactions between
the system bus and the PCI buses using 32-byte buffers for inbound
and outbound postings. The use of two OPBs in the system creates
an architecture that allows faster data transfers.
Orion Memory Controller
The Orion memory controller (OMC) acts as an interface between the
system bus and the system memory. It consists of the DRAM
control (DC) chip and the data path (DP) chip. The OMC relates to
the DRAM array through four memory interface controller (MIC) chips.
The OMC supports 256-bit 4-way memory interleaving resulting to a
more efficient memory traffic management.
1.1.3 SCSI Disk Array
The system supports an array of eight hot-swappable disk drive trays
through an 8-slot SCSI backplane board. The trays accommodate
wide and narrow SCSI hard disks. With the AIC-7880 SCSI controller
onboard, the transfer rate reaches up to 40 MB per second for ultra
SCSI and 20 MB per second for wide SCSI.