ND-210412 — ND-500/1 CXA Microprogram

Status: IN-PROGRESS — real floppy decoded; notable cross-reference to the ND-500 microcode preservation project

Field	Value
ND article number	ND-210412
Product name	ND-500/1 CXA Microprogram
Functional category	Hardware / Microcode (not a language/dev tool — logged here as it turned up in the same floppy sweep)
CPU target	ND-500/1 (CXA control unit)
Related products	ND-805013 Single Precision Array Processing Functions (see ../../../Reference-Manuals/500/ND-805013-3 EN ND-500 Single Prec. Array Proc. Func..md) — ND-500-APF-LIB must be loaded together with this microprogram.

What is known — real floppy, decoded

Floppy 210412F01-XX-01S (downloaded via NDwiki, imaged by Torfinn "Tingo" Ingolfsen) mounts cleanly, files owned by user SYSTEM:

CONT-STORE-10611:DATA      the microcode control-store image itself
ND-500-APF-LIB-E:NRF       the Array Processing Function library (see ND-805013 above)

CONT-STORE-10611:DATA matches the exact filename this repo's ND-500 microcode preservation work already treats as "the only surviving real ND-500 (144-bit microword) control store" — see the nd500-microcode skill and E:\Dev\Ronny\ND500UC. This floppy is very likely a — or the — original source for that file, found independently via a different route (NDwiki, not the floppies.json reference library). Not cross-checked byte-for-byte against the copy already in use by that project — if the two differ at all, that would be significant and worth flagging to that project directly; this catalog entry only records that the file exists here too.

Documentation

• No PD sheet, no PI sheet located in this catalog's archive for this specific article number.

Provenance & open items

• Source: one real floppy image, downloaded via NDwiki and decoded in this session (ndfs -t).
• TODO: byte-for-byte comparison against the CONT-STORE-10611.DATA already used by the ND-500 microcode toolchain has not been done — see the nd500-microcode skill for that project's own verification method (round-trip disassemble/reassemble/byte-compare).

---

Parent: ../README.md (Software catalog)