Digital Equipment DECmpp 12000/Sx 100, Руководство по обслуживанию оборудования

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2.3 Indicators
The chassis ground circuit detects differences in potential between chassis ground
and logic ground and shuts down the power tray when the potential exceeds a
preset 70 mV threshold.
2.3.2.2 Array Control Unit PCB Indicators
Figure 2–5 shows indicator locations on the array control unit (ACU) PCB. The
12 indicators on the ACU PCB are arranged in three groups of four (Figure 2–7).
Table 2–3 lists the ACU indicator functions (from the top).
Figure 2–7 Array Control Unit PCB Indicators
MKV−040000314−56−RAGS
Power
Bus Grant
Microcode Interrupt
Any_Reg
Data Strobe
DTACK
IBUSY
BUSERR
MMSEL
Mempty
IFUVAL
Address Strobe
2–10 DPU Controls and Indicators