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47 lines
1.7 KiB
Plaintext
Executable File
47 lines
1.7 KiB
Plaintext
Executable File
Conventions for relations between KLDCP and IOELEV
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Core locations -
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3000 KLDCP does JSR PC, here when it has nothing to do
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and 10 is running. IOELEV should INIT if it hasn't
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already, then go into its main loop. It should CLC, RTS PC
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if the 10 goes down; KLDCP will print appropriate message.
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To go into temporary KLDCP command mode, SEC, RTS PC.
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If microcode hangs, PMSG <...>, JMP 100004 (CTRLC).
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3004, 3006 - .RAD50 /IOELEV/
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3010, 3012 - random crufty version numbers (not actually used)
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14, 16 BPT vector, I guess it's OK for 11 ddt to use these.
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.. interrupt vectors for various devices are initially set
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up by KLDCP to point to error routine; IOELEV can load
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over these.
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0-400 vectors
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3000-? IOELEV (what is 400-3000 used for?)
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?-100000 11 DDT
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100000-? KLDCP
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?-160000 stack
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KLDCP will supply IOELEV with a stack; 11 DDT will have to be modified
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to believe it.
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Even while the IOELEV main loop is not running, interrupts will be
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turned on and IOELEV P.I. level can run. Various things like "MR" will
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do a pdp11 "RESET" instruction and flush this. This allows the right thing
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to happen if the 10 halts, you go to KLDCP, in KLDCP you type DDT, and
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now you're back in IOELEV.
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Consequently IOELEV has to handle the flavor of teletype that DDT & SALV use.
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It's best to do an "RI" before running, e.g., DEC diagnostics.
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IOELEV isn't allowed to turn on interrupts for any devices that KLDCP
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also uses; mainly, 60-cycle clock and DTE20. These have to be handled
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entirely in the main program and not touched at all at P.I. level (since
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IOELEV's P.I. level runs concurrently with KLDCP.)
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IOELEV main program level can (and will) use KLDCP's EMT's to hack the DTE20.
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