Home / feilipu / 8085-skills · .agents/skills/compiler-ac85/SKILL.md · GitHub

compiler-ac85 skillA

compiler-ac85 is agent-read markdown (skill) from feilipu/8085-skills: Agent compiler for Intel 8085 (ac85): emit Zilog assembly for z88dk-z80asm -m8085 from standard C90. Data model, SMALLC ABI, stack frames, HL as ALU bus, BC/DE parking, 8085 extended ops, C90 shape → ISA lowering. Use for /compiler-ac85, "agent compiler 8085", "C compiler guide for 8085", "compile this C to 8085 assembly", "8085 C lowering". Do not use when invoking zcc, 80cc, or sccz80 as the compiler, or when editing src/80cc (those are compiler-80cc, compiler-sccz80, tool-zcc)..

Indexed from public GitHub and served as immutable, content-addressed versions. Install it pinned to an exact SHA-256 with the mdr CLI, and every file is verified against the hash recorded here before it reaches your agent. The deterministic audit below grades the latest version, and the same file always earns the same grade.

What the file says

# C compiler guide — 8085

Compile **ISO C90** to **Zilog** 8085 assembly that `z88dk-z80asm -m8085`
accepts. Load **`cpu-8085`** for the opcode map, flag effects, timings, and
stack-access sequences. This card is the **C** layer: types, ABI, register
assignment, and how C constructs map onto that ISA.

Optimise from the **8085 instruction set**, not from Z80 habit. Extended
ops (`ld de,sp+*`, `ld hl,(de)`, `ld (de),hl`, `sub hl,bc`, `rl de`,
`sra hl`, `jp k` / `jp nk`) are first-class on every 8085. There is no IX,
no `exx`, no native `djnz`, and no 2-byte `jr` (`18` is `rl de`). Assembler
`jr` becomes a 3-byte `jp`. **8085-only listings write `jp`.** Dual-CPU
library source may write `jr` (`cpu-8085`).

**Shape before statements.** Name the C90 shape in a function (walking
byte array, word swap, pre-dec-to-zero, struct cursor, …) and emit the
ISA sequence for that shape. Do not lower a naïve `a[i]` / `i++` form
when the shape is a pointer walk or an induction.

## C data model on 8085

Default **`char` is signed**. Little-endian. Integer promotions go to
16-bit `int`. `short` is 16-bit (same home as `int`). Struct members:
`offset += size` (no 2-byte ABI holes).
…

Read the whole file at its exact version.

How to install

Latest version
mdr add feilipu/8085-skills/compiler-ac85@git:20260921.85b9514
Exact content
mdr add feilipu/8085-skills/compiler-ac85@sha256:c0611bf9ed9f10d6

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Versions

versioncommittedcommitsizeaudit
git:20260921.85b9514 latest2026-09-21 85b9514 65,417 BA view · diff
git:20260921.2f39ee62026-09-21 2f39ee6 64,958 BA view · diff
git:20260920.88ac0a12026-09-20 88ac0a1 62,676 BA view · diff
git:20260920.d8931322026-09-20 d893132 61,204 BA view · diff
git:20260919.24cc48b2026-09-19 24cc48b 45,005 BA view · diff
git:20260919.216763a2026-09-19 216763a 43,321 BA view

Audit of the latest version

A  17 of 17 checks passed. Deterministic, no model, same answer every run.
  • pass: Frontmatter block present
  • pass: Frontmatter declares a name
  • pass: Frontmatter declares a description
  • pass: Size between 200 bytes and 200 KB (65417 bytes)
  • pass: No zero-width or bidi control characters
  • pass: No instruction hidden inside an HTML comment
  • pass: No link to an exfiltration or paste host
  • pass: No credential-shaped string
  • pass: No instruction to send local credentials anywhere
  • pass: No text hidden with inline styles
  • pass: No prompt-injection phrasing
  • pass: No curl or wget piped into a shell
  • pass: No recursive delete of root, home or parent
  • pass: No instruction to read or print local credentials
  • pass: No base64 blob over 200 characters
  • pass: No link to a raw IP address
  • pass: No script tag

Source

GitHub

feilipu/8085-skills · 3 stars · license MIT · pushed 2026-09-21 · branch main

API

GET https://markdownregistry.com/api/v1/artifacts/art_vb6csfbmil7cesbl
GET https://markdownregistry.com/api/v1/resolve?ref=feilipu/8085-skills/compiler-ac85
GET https://markdownregistry.com/api/v1/blob/c0611bf9ed9f10d6f1fe07cc5b5588148401967bdb56a846feb6f49bace508e4

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