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MON 11B (octal) - TIME (GetBasicTime)

Returns the internal clock value in basic time units (a double word). One of the clock/time family (TIME, CLOCK, XPERC, PERCE, DPERC) that share a common body in 003-S3CP. All addresses/values are octal.

Status: byte-verified (dispatch chain + worker entry). The worker is real carved code in 003-S3CP.

CORRECTED 2026-07-13. Earlier versions of this folder were built on the disproven "uncarved CALLPROC bridge / GOTAB is the monitor-call table" model (they claimed GOTAB[11B]=120427B -> P04R2 and a "zero-filled TIME region"). That was fiction. MON calls dispatch through MCTAB @ 005620B (segment 044-S3IDPIT), not through GOTAB (which is MFELL for 224 of 256 calls). MCTAB[11B] = 040747B = TIME, and that worker IS carved in 003-S3CP. See ../317B-ExecuteCommand/README.md and SINTRAN/CARVING-HANDOFF.md section 3a.

Dispatch path

flowchart LR
    A["User program<br/>MON 11B"] --> B["ENT14 level-14 entry<br/>026-S3IMPIT :072167B"]
    B --> C["GOTAB[11B] = MFELL<br/>MGOTA=071233B :071244B"]
    C --> D["MFELL level switch<br/>026-S3IMPIT :072114B -> CALLP 032201B"]
    D --> E["MCTAB[11B] = TIME<br/>MCTAB=005620B :005631B = 040747B"]
    E --> F["TIME worker<br/>003-S3CP :040747B"]
    class A blue
    class B,C,D,E teal
    class F green
    classDef blue fill:#E3F2FD,stroke:#0D47A1,color:#0D47A1
    classDef teal fill:#E0F7FA,stroke:#00838F,color:#00838F
    classDef green fill:#E8F5E9,stroke:#2E7D32,color:#2E7D32

Code location (dispatch path)

Byte offset = (addr - loadbase) in octal words x 2 (decimal). Every offset was reproduced with dd.

Role Segment Addr (octal) Byte offset Symbol Verdict
GOTAB[11B] slot 026-S3IMPIT.asm 071244B = 072114B 32072 -> MFELL VERIFIED
MFELL level switch 026-S3IMPIT.asm 072114B 32920 MFELL VERIFIED
MCTAB[11B] slot 044-S3IDPIT.asm 005631B = 040747B 1842 -> TIME VERIFIED
TIME worker body 003-S3CP.asm 040747B-040755B 9166 TIME VERIFIED

Verify by hand (from tools/sintran-segment-carver/versions/L-VSX-500/segments/): 

dd if=026-S3IMPIT.bin bs=1 skip=32072 count=2 | od -An -tx1   ->  74 4c   (= 072114B = MFELL)
dd if=044-S3IDPIT.bin bs=1 skip=1842  count=2 | od -An -tx1   ->  41 e7   (= 040747B = TIME)
dd if=003-S3CP.bin    bs=1 skip=9166  count=2 | od -An -tx1   ->  41 a3   (= 040643B, TIME entry word)

Instruction walkthrough

Full listing: 11B-GetBasicTime.ASM.

Entry (040747B-040750B). 040643 MIN ,B -135 increments a mode/selector counter in the caller frame (this is the family's "which time function" discriminator), then 026777 LDD ,X ,B -1 loads a double word. Control falls through into the shared prologue.

Shared prologue SM2DE (040751B). 146141 RADD CLD SL DD copies the return link L into D, then 135741 JPL I ,B -37 calls the common timer body (pointer at frame -37, target 040713B = TMOUT). The following RADD CLD SA DD / RADD CLD 0 DA / SAT 12 stage the result and a unit code before returning.

The TIME/CLOCK/XPERC/PERCE/DPERC entries are short stubs that select a mode and share one body - the same "one body, per-entry mode code" idiom documented for the COMSB/UECOM/UELOG cluster in ../317B-ExecuteCommand/README.md. The result is returned as the internal clock in basic time units (per the manual).

Parameter / register contract

Reg / field Dir Meaning Verdict
,B -135 frame family mode/selector counter (MIN ,B -135) VERIFIED (bytes); meaning inferred
L in return link, saved via SM2DE (RADD CLD SL DD) VERIFIED (bytes)
result (A/D) out internal clock in basic time units (double word) VERIFIED (manual); staging bytes VERIFIED, exact packing inferred
shared body - reached by JPL I ,B -37 -> 040713B (TMOUT), not carved in this folder VERIFIED (call site); body inferred

Pseudo-code (for an emulator)

See 11B-GetBasicTime.pseudo.c. The entry stub, the mode counter and the shared-prologue call are byte-verified; the timer-body internals are inferred (that body at 040713B is reached by JPL I ,B -37 and is not carved in this folder).

Honest caveats

What is byte-proven: the full dispatch chain - GOTAB[11B] = MFELL, MFELL switches program level to CALLP, MCTAB[11B] = TIME = 040747B, and the TIME entry bytes at 040747B in 003-S3CP match the disassembly. TIME is one entry of a five-entry clock family sharing a common body.

What is NOT proven: the internal layout of the shared timer body (TMOUT at 040713B, not carved here), the exact bit-packing of the returned double word, and the manual's semantics (basic time units). Those come from structure and the manual, not these bytes.

Method: ../../../../../EXTRACTING-RESIDENT-CODE.md · master map: ../../MON-CALL-INDEX.md.