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MON 113B (octal) - CLOCK (GetCurrentTime)

Returns the current system time and date. CLOCK is one of the clock/time family (TIME, CLOCK, XPERC, PERCE, DPERC) that share a common body in 003-S3CP; the CLOCK path performs the calendar/time-of-day conversion (divide + decimal scaling). 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 used the disproven dispatch model (GOTAB as the monitor-call table, an "uncarved CALLPROC bridge"). MON calls dispatch through MCTAB @ 005620B (segment 044-S3IDPIT), not GOTAB (which is MFELL for 224 of 256 calls). MCTAB[113B] = 040756B = CLOCK, 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 113B"] --> B["ENT14 level-14 entry<br/>026-S3IMPIT :072167B"]
    B --> C["GOTAB[113B] = MFELL<br/>MGOTA=071233B :071346B"]
    C --> D["MFELL level switch<br/>026-S3IMPIT :072114B -> CALLP 032201B"]
    D --> E["MCTAB[113B] = CLOCK<br/>MCTAB=005620B :005733B = 040756B"]
    E --> F["CLOCK worker<br/>003-S3CP :040756B"]
    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[113B] slot 026-S3IMPIT.asm 071346B = 072114B 32204 -> MFELL VERIFIED
MFELL level switch 026-S3IMPIT.asm 072114B 32920 MFELL VERIFIED
MCTAB[113B] slot 044-S3IDPIT.asm 005733B = 040756B 1974 -> CLOCK VERIFIED
CLOCK worker body 003-S3CP.asm 040756B-040765B 9180 CLOCK VERIFIED

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

dd if=026-S3IMPIT.bin bs=1 skip=32204 count=2 | od -An -tx1   ->  74 4c   (= 072114B = MFELL)
dd if=044-S3IDPIT.bin bs=1 skip=1974  count=2 | od -An -tx1   ->  41 ee   (= 040756B = CLOCK)
dd if=003-S3CP.bin    bs=1 skip=9180  count=2 | od -An -tx1   ->  c3 b0   (= 141660B, CLOCK entry word)

Instruction walkthrough

Full listing: 113B-GetCurrentTime.ASM.

Entry (040756B-040765B). 141660 RDIV ST divides (the time-of-day conversion: split the raw clock into higher/lower units), 146117 RADD CLD SD DX moves the quotient into X, then 172460 AAA 60 and 135005 JPL I 5 (-> 040766B = XPERC) call the shared conversion helper. 170460 SAA 60 / 146075 RADD SX DA / 135002 JPL I 2 (-> 040766B) repeat the step for the next field. The neighbouring XPERC/PERCE/DPERC code (040766B-041051B) performs the divide-by-powers-of-ten decimal breakdown (normalize loop, MPY/RDIV, SAA 144 = 100 decimal) that turns the raw counter into calendar fields.

CLOCK shares the SM2DE/TMOUT common prologue with TIME (see the 11B folder). It returns the current time and date fields per the manual.

Parameter / register contract

Reg / field Dir Meaning Verdict
A/X in/out raw clock feeding RDIV, quotient staged to X VERIFIED (bytes)
caller buffer out current time and date fields VERIFIED (manual); field layout inferred
shared conversion - JPL I 5/JPL I 2 -> 040766B (XPERC decimal breakdown) VERIFIED (call sites)

Pseudo-code (for an emulator)

See 113B-GetCurrentTime.pseudo.c. The divide/convert entry and the calls into the decimal-breakdown helper are byte-verified; the exact calendar-field packing and the caller-buffer layout are inferred from the manual.

Honest caveats

What is byte-proven: the full dispatch chain - GOTAB[113B] = MFELL, MFELL switches program level to CALLP, MCTAB[113B] = CLOCK = 040756B, and the CLOCK entry bytes at 040756B in 003-S3CP match the disassembly. CLOCK uses the adjacent XPERC/PERCE/DPERC decimal-scaling code and shares the TIME family prologue.

What is NOT proven: the exact set/order of returned calendar fields, the caller-buffer layout, and the full internals of the decimal-breakdown helper. Those come from structure and the manual, not these bytes.

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