Digital Equipment Prioris XL 6000 Series, Service Maintenance Manual

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Block Diagram
E-6
Diskette Controller
The Super I/O also has a floppy disk drive (FDD) controller which supports two
diskette drive devices through a daisy-chained ribbon cable. Data transfer rates are
selectable to be 250/300 Kb/s or 500/1000 Kb/s. These rates are compatible with the
5.25” and 3.5” diskette drives. The 5.25” FDD includes high-capacity 1.2MB and low-
capacity 360 KB formats. The 3.5” FDD includes 720KB, 1.44MB, and 2.88MB
formats.
Super Video Graphics Array
The main logic board has a Super Video Graphic Array (SVGA) Trio32 or Trio64 V+
family video controller. It uses an S3 VGA graphic user interface (GUI) accelerator
and is 100% register-level compatible with IBM VGA. It provides:
•
Advanced architecture using pipelining, multiple FIFO, and a read-ahead cache
•
Hardware acceleration of 2-D graphics
•
Direct connectivity to 32-bit local bus
•
Full hardware and BIOS support for VESA Display Power Management
(DPMS)
•
Fast linear addressing by the CPU for up to 1 MBytes of display memory
(256K x 16, 60 ns DRAM)
The following table lists the SVGA connector pin assignments.