Pass 1. The project builds and verifies byte-identical to the original ROM. prg.s is a traced disassembly classifying bytes as reachable code or data, with every instruction carrying a trailing audit comment. Unreached bytes remain as explicit .byte blocks; no ROM byte is deleted or reformatted.

make assembles header.s, prg.s, chr.s, links them with ld65 and compares the result against rom.nes:

Byte-identical ROM verified.

ROM

Property	Value
Format	iNES
Mapper	0
Board	NROM-256
Mirroring	Vertical
Four-screen VRAM	no
Battery	no
PRG	32 KB (2 x 16 KB), mapped at CPU $8000-$FFFF
CHR	8 KB (1 x 8 KB)
Trainer	none
Footer	none
NMI vector	$8082
RESET vector	$8000
IRQ vector	$FFF0
ROM file	`Super Mario Bros (JU) (PRG 0).nes`
SHA-256	`f61548fdf1670cffefcc4f0b7bdcdd9eaba0c226e3b74f8666071496988248de`

Header notes

none

Open work

Pass 1 - run nesdis.py over prg.bin to produce the code/data split. The tracer reads the vectors from the last six bytes of the PRG image, so the split seeds correctly.
Pass 1 must emit the canonical audit comment ; CPU:$C123 PRG:0123 AD 21 03 at column 35 for every instruction.
Pass 2 - replace the address-derived Label_XXXX names and the raw $XXXX call operands.
Pass 3 - semantic zero-page aliases (applied only at the sites where their role is proven) and named data tables.
Promotion to NROM/<name>/ once Pass 3 is done, as git mv.

Files

File	Purpose
`prg.s`	Pass 0 PRG include (replaced by the Pass 1 disassembly)
`header.s`	iNES header include
`chr.s`	CHR include
`prg.bin`	32768 bytes (32 KB) PRG image
`chr.bin`	8192 bytes (8 KB) CHR image
`rom.nes`	byte-identical copy of the original ROM
`linker.cfg`	HEADER / PRG / CHR memory areas
`symbols.inc`	NES hardware register names
`locals.inc`	zero-page aliases (empty at Pass 0)
`Makefile`	build and byte-identity check