Digital Equipment DEC 3000 600 AXP, Service Information

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Overview
Addresses generated by DMA devices in the I/O system may be
translated by a scatter/gather map. The scatter/gather map can
map 32 KB pages. This translation is optional, enabled on a
device-by-device basis.
Serial Lines: The serial line interface supports the following
equipment:
Equipment Connections
Keyboard Connects to a 15-pin D-sub connector.
Mouse Shares 15-pin D-sub connector with
keyboard.
Printer Connects to a 6-pin MMJ and is DEC–
423 compliant.
Communication port Connects to a 25-pin D-sub connector
and supports full modem control.
Ethernet Interface: The Ethernet interface can connect to
the local area network (LAN) by using an attachment unit
interface (AUI, or thickwire) or 10BASE-T twisted-pair cable.
The selection (thickwire or twisted pair) is software-controllable.
SCSI Interface: The SCSI interface consists of two separate
channels using two SCSI-2 controller chips (53CF94). These
controller chips connect to the TURBOchannel through an
ASIC. The ASIC buffers data to and from the SCSI controllers,
providing 16-longword DMA bursts across the TURBOchannel
for increased bus efficiency.
ISDN and Audio In/Out: An AMD 79C30A controller chip
provides an ISDN interface and telephone-quality audio input
and output. Jacks and connectors in the front of the unit provide
connections for a microphone and headphones.
Battery Backed-Up TOY: A battery backed-up time-of-year
(TOY) chip provides a time reference when the unit is turned off.
The TOY also provides 50 bytes of non-volatile RAM (NVR) for
system parameters.
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