AT&T 6300 Service Manual page 209

DIAGNOSTICS
DIAGNOSTIC MESSAGE MEANING
RT Clock Fail
MM58174 registers not functioning
RT Clock Fail:NR 8253 interrupt did not respond
RT Clock Fail:LO
8253 interrupt is out of specifi­
cation on the low end
RT Clock Fail:HI 8253 interrupt is out of specifi­
cation on the high end
Figure 4-1. Resident Diagnostic Messages (Sheet 2 of 5)
DIAGNOSTIC MESSAGE MEANING
Floppy (A:) Not Ready
Diskette not present or
faulty MFD Unit A
Fixed Disk Not Present Faulty HDU
Figure 4-1. Resident Diagnostic Messages (Sheet 3 of 5)
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