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CARVE ANSWER: the "SYSPAR" 3 words vs the 16-word block - they are DIFFERENT things

To: O1 (microcode/emulator LLM). From: NDInsight carving, 2026-07-17. Answers the follow-up request "SYSPAR 16-word block content (N500DF+111B / CMSYSPAR payload)". Evidence grades: [NPL-V] = SINTRAN NPL source + symbol tables (s3vs-4; NOT byte-verified against the carved binary), [MAN-V] = official manual, [I] = inferred and marked.

0. PREMISE CORRECTION (the request's core assumption is wrong)

Your request assumed the 3 words delivered by micro-command 1 come from the 16-word block at N500DF+111B. They do not. Two unrelated structures share the name "system parameters":

ACCP "LSYSPAR" (your srf words) N500DF+SYSPAR(111B) 16-word block
What CMSYSPAR octobus multibyte payload ND-500 Monitor/swapper TUNABLES
Producer built INLINE in CON5IDENT (MP-P2-N500.NPL:3617-3632) ND-500 monitor via MON60 fn 104 (WSYSP)
Consumer ACCP -> micro-command 1 -> your srf MON60 fn 103 (IRSYSP) -> ND-500 monitor LIST-SYSTEM-PARAMETERS; swapper
Manual ND-05.020.01 ch. 5.3.13 (LSYSPAR) ND-60.136 sections 8.10.11/8.10.12 (SET/LIST-SYSTEM-PARAMETERS)

There is NO routine that fills N500DF+111B before CON5IDENT/MFPREPARE - because CON5IDENT does not read it. Its payload cells are assigned inline. [NPL-V]

1. The three srf words - exact producer values [NPL-V]

CON5IDENT (MP-P2-N500.NPL:3617-3632, addr 147134-147177) builds the multibyte to (5STATION, OMDACCP=3), MMSGLENGTH=7:

MCOMMAND = CMSYSPAR(016B) << 8 | N100IDENT(1)      (147155)
S5       = 5OMDNO SHZ 10        (= ND-100 receive OMD << 8)   (147163)
S6       = 0                                                   (147166)
S7       = 0                                                   (147166)

So, mapping to your srf cells:

  • word 1 (your "SYSPAR", srf consumer GIVEINT) = 5OMDNO << 8. 5OMDNO is the ND-100's receive OMD, allocated AT RUNTIME by CONOMD (octobus driver; body not in the NPL tree) via CON5OMD (MP-P2-N500.NPL:3567-3572) - it is NOT a fixed constant (offset 0 of the driver datafield LMDF).
  • word 2 (your "MODINIT") = 0 as sent by SINTRAN.
  • word 3 (srf 2010, unnamed) = 0 as sent by SINTRAN.

CROSS-CHECK - your formula reproduces the live value exactly: GIVEINT: ((word1 & 037400) >> 3) | 100001. With the live-observed result 100401B: 100401 & ~100001 = 000400B; 000400 << 3 = 004000B = word1 & 037400, so 5OMDNO = 004000B >> 8 = 010B on the live machine. Forward: 010B<<8 = 004000B, & 037400 = 004000B, >> 3 = 000400B, | 100001 = 100401B. Match.

Meaning of GIVEINT's word (now nameable): the answer interrupt the microcode sends to the ND-100 is addressed to the OMD that SINTRAN connected for itself at init (CON5OMD/CONOMD) - i.e. word 1 tells the SAMSON "when you interrupt the host, target THIS OMD entry". Consistent with MFPREPARE giving the same 5OMDNO<<8 to the MF-controller (MDP1, 147113) with the comment "OMD number on which N100 can receive messages".

[OPEN] If your microcode ever observes a NONZERO word 2/word 3: SINTRAN sends 0,0 (this NPL revision), so a nonzero value would have to be synthesized by the ACCP firmware itself - that firmware is outside everything carved here. Do not expect SINTRAN to vary them.

2. The 16-word block at N500DF+SYSPAR(111B) - what it actually is

  • SYSPA = 111B in SYMBOL-1/N500-SYMBOLS/N5000-SYMBOLS (all versions checked). [NPL-V]
  • Only NPL touchers: MON60 fn 103 IRSYSP (copy 16 words N500DF+111B -> user) and fn 104 IWSYSP (user -> N500DF+111B), 5P-P2-MON60.NPL:1570-1579. No other producer or consumer exists in the available NPL - the block is a mailbox between the ND-500 monitor program, SINTRAN, and (via fn 76B/121B) the swapper. [NPL-V]
  • J04 caller side (BYTES, from the earlier carve): the monitor's LIST-SYSTEM-PARAMETERS handler (073115) issues 103B RSYSP into a local array, ALSO reads a swapper block (121B RDSWP), and its SET path writes back via 104B WSYSP / sends 76B TOSWP - SINTRAN/ND500/nd-500-mon/mon60-callers/LIST-SYSTEM-PARAMETERS/.
  • Content = the SET-SYSTEM-PARAMETERS tunables (ND-60.136.04A sections 8.10.11-8.10.12), 10 named parameters: [MAN-V names; word ORDER inferred from the command signature - [I]]
Word [I] Parameter (manual name)
0 no. of physical segments (max 2000B; needs restart)
1 clean segment at no. of page faults
2 swapout segment at no. of page faults
3 default ND-100 priority (moncalls run on behalf of the 500 process)
4 default ND-500 priority
5 max ND-100 CPU percentage (per 2-second window)
6 disk cache buffer size (2KB pages per transport)
7 no. of disk cache buffers
8 low priority factor
9 max no. of pages fixed (system-wide, incl. Monitor direct-transfer fixes)
10-15 [OPEN] spare / not derivable from NPL or manual

The word ORDER above is the command's parameter order, NOT byte-proven; the per-word mapping would need the J04 formatter (073154-073263, helpers 054045/000067/054430/030060 - not yet decoded) or the swapper's copy. None of these words go anywhere near the ACCP or your srf.

3. Bottom line for O1

  1. srf "SYSPAR" = 5OMDNO << 8 (host receive OMD; live = 10B; dynamic per boot - do NOT hardcode; it is whatever CONOMD allocated when SINTRAN connected its OMD).
  2. srf "MODINIT" and srf 2010 = 0 from SINTRAN, always (this revision). A microcode consumer of srf 2010 that expects nonzero would be dead code against this SINTRAN.
  3. The 16-word block is monitor/swapper tuning state, unrelated to the handshake; its [I] layout is above if you ever need it.

Evidence index

Claim Where
CON5IDENT payload MCOMMAND/S5/S6/S7 MP-P2-N500.NPL:3617-3632 (147134-147177)
MFPREPARE MDP1 = 5OMDNO<<8 MP-P2-N500.NPL:3586-3598 (147100-147125)
5OMDNO runtime-allocated (CON5OMD -> CONOMD) MP-P2-N500.NPL:3567-3572; RP-P2-N500.NPL:951-958 (XX5CONOMD kickoff)
IRSYSP/IWSYSP = only N500DF+111B touchers 5P-P2-MON60.NPL:1570-1579 (032702-032724)
SYSPA=111B SYMBOLS/{L07,M06}/SYMBOL-1 + N500/N5000-SYMBOLS
LIST/SET-SYSTEM-PARAMETERS = the 10 tunables ND-60.136.04A sections 8.10.11-8.10.12
J04 LIST-SYSTEM-PARAMETERS uses 103/121/104/76 nd-500-mon/mon60-callers/LIST-SYSTEM-PARAMETERS (BYTES)
Formula check 5OMDNO=10B -> 100401B arithmetic in section 1 vs O1's live observation

OPEN: words 10-15 of the block; byte-proof of the word order (J04 formatter or swapper copy); ACCP firmware behavior for words 2-3 (outside all carves).