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55 lines
1.9 KiB
Plaintext
Executable File
55 lines
1.9 KiB
Plaintext
Executable File
Copyright (c) 1999 Massachusetts Institute of Technology
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See the COPYING file at the top-level directory of this project.
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------------------------------
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KL10 Folklore
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Sometimes an MF10 memory gets hung. Often the INC RQ light will be
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on. Sometimes raising the RESET switch inside the memory's front door
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will help; sometimes a module in the port control is fried. (Any of
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several modules.)
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TU41 blower belt has to correct belt, has to not be worn out, and has
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to have pulleys aligned. Otherwise it drops off or breaks and tape
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rotates backwards.
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RP04 oscillating seeks & Maytag mode when loading => tachometer output
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needs to be adjusted.
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When powering machine back on, circuit breaker in disk DF10 may trip.
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When powering machine back on, sometimes disk #0 needs to be stopped,
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powered off and on, and started again, to reset the two-massbus
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switch.
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If DECtape motor doesn't win, may be G848 seating problem.
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If kicking the LA36 causes power fail, "power warn" lead to top left
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edge of CPU backplane needs to be disconnected. (Apparently the other
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end is unconnected.) [Missing ECO in 863.]
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Bad door-open switches (?) in MF10. Memories have to be operated with
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over-ride turned on.
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Apparently power supplies in CPU and IO box can drift voltages.
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Apparently air-flow sensors can fail sporadically. I am told that
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disconnecting one => indication of good airflow.
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RP04 attention/error conditions are super-random.
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Often mysterious marginality is caused by bad seating of modules.
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CONO'ing a PI channel off doesn't necessarily prevent it from
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interrupting. It works to have each interrupt routine do CONSO to make
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sure the channel is enabled, and dismiss if not.
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Before running a memory diagnostic, do PE0, because the memory
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diagnostics don't know how to handle parity faults.
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MF10's always fail solidly.
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Obscure cases in the microcode tend to have bugs. E.g. you could
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interrupt out of a PI cycle, hence BLKI/BLKO as interrupt instructions
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tended to be flakey.
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