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Controls and Indicators
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)
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