Technical data

Functional Description
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Support functions for the 53C710 are provided by the MC2chip. Refer to
the NCR 53C710 user’s guide and to the MC2chip in the MVME172 VME
Embedded Controller Programmer’s Reference Guide for detailed
programming information.
SCSI Termination
It is important that the SCSI bus be properly terminated at both ends.
The MVME172LX main board provides terminators for the SCSI bus. The
SCSI terminators are enabled/disabled by a jumper on header J12. If the
SCSI bus ends at the MVME172LX, a jumper must be installed between
J12 pins 1 and 2.
The
FUSES LED (part of DS2) on the MVME172LX front panel monitors
the SCSI bus
TERMPWR signal in addition to LAN power and
IndustryPack power; the
FUSES LED illuminates when all fuses are
operational. The fuses are solid-state devices that reset when the short is
removed.
Because any device on the SCSI bus can provide TERMPWR, the
FUSES
LED does not directly indicate the condition of the fuse.
Local Resources
The MVME172LX includes many resources for the local processor. These
include tick timers, software-programmable hardware interrupts, a
watchdog timer, and a local bus timeout.
Programmable Tick Timers
Four 32-bit programmable tick timers with 1µs resolution are provided in
the MC2chip and two 32-bit programmable tick timers are provided in the
optional VMEchip2. The tick timers may be programmed to generate
periodic interrupts to the processor. Refer to the VMEchip2 and MC2chip
in the MVME172 VME Embedded Controller Programmer’s Reference
Guide for detailed programming information.