user manual
Controls and Indicators
3-3
3
Front Panel Indicators (DS1 - DS4)
There are eight LEDs on the MVME177 front panel: FAIL, STAT,
RUN, SCON, LAN, +12V (LAN power), SCSI, and VME. The
purpose of each LED is as follows:
❏ The red FAIL LED (part of DS1) lights when the BRDFAIL
signal line is active
❏ The MC68060 status lines are decoded, on the MVME177, to
drive the yellow STAT (status) LED (part of DS1). In this case,
a halt condition from the processor lights the LED
❏ The green RUN LED (part of DS2) lights when the local bus
TIP* signal line is low. This indicates one of the local bus
masters is executing a local bus cycle
❏ The green SCON LED (part of DS2) lights when the
VMEchip2 in the MVME177 is the VMEbus system controller
❏ The green LAN LED (part of DS3) lights when the LAN chip
is local bus master
❏ The MVME177 supplies +12V power to the Ethernet
transceiver interface through a fuse. The green +12V (LAN
power) LED (part of DS3) lights when power is available to
the transceiver interface
❏ The green SCSI LED (part of DS4) lights when the SCSI chip
is local bus master
❏ The green VME LED (part of DS4) lights when the board is
using the VMEbus (VMEbus AS* is asserted by the
VMEchip2) or when the board is accessed by the VMEbus
(VMEchip2 is the local bus master)