Factual cross-check and caveats

Metadata

Field	Value
source	../deep-research-report.md
document	Deep Research Report: It Took Every SNES Hardware Trick To Make My Game — Inkbox
kind	section-lead
parent
lines	296-316
video	https://www.youtube.com/watch?v=j_2bo7ng65E
findings	D13-C3 D13-M1 D13-M7 D13-m1 D13-m9 D13-m10

Source video: It Took Every SNES Hardware Trick To Make My Game (Inkbox, 51:14) · at 20:58. The video says ‘my 4 megabyte cartridge ROM’ here. It never claims a hardware limit or a 3.58 MHz 6502.

Claim or theme associated with the video	Assessment	Cross-check
“The SNES uses a 3.58 MHz 6502-based CPU.”	Partly correct, but imprecise.	The console CPU is the Ricoh 5A22, derived from the WDC 65C816 family. Calling it “6502-based” describes its ancestry, but “65C816-derived” is much more precise. Its effective rate is also not constantly 3.58 MHz; slower accesses can reduce the effective clock. citeturn26search14turn27search4
The system has 128 KiB of work RAM, effectively banks `$7E–$7F`.	Correct.	SNESdev documents the two banks as providing a continuous 128 KiB WRAM region. citeturn28search4
There is a 4 MB cartridge limit.	Needs qualification.	Ordinary LoROM supports up to 4 MiB, and conventional HiROM has a comparable limit, but SNESdev explicitly documents ExHiROM as a mapping for exceeding 4 MiB. Treating 4 MiB as a chosen/conventional historical constraint is sound; calling it an absolute SNES hardware limit is not. citeturn28search4
Mode 1 gives three background layers, with two 4-bpp and one 2-bpp.	Correct.	SNESdev lists Mode 1 as BG1=4 bpp, BG2=4 bpp, BG3=2 bpp and calls it the most commonly used background mode. citeturn28search9
Mode 1 can use 16×16 background tiles.	Correct.	The background documentation lists selectable 8×8 or 16×16 tile sizes for the relevant background layers. citeturn28search9
HDMA can alter scrolling/display state at particular screen lines.	Correct.	SNESdev states that HDMA can automatically write hardware-register values at specific scanlines; its documented transfer patterns include scroll-position registers. citeturn37search6
SNES audio has a separate SPC700-based processor with 64 KiB audio RAM.	Correct.	The S-SMP documentation identifies the Sony SPC-700, 64 KiB Audio-RAM and CPU/APU communication ports. citeturn33search8
The sound DSP has eight voices.	Correct.	SNESdev explicitly documents eight S-DSP voices numbered 0–7. citeturn33search8turn33search20
Samples use BRR compression.	Correct.	SNESdev documents BRR as the native S-DSP sample format, using 16-sample blocks stored in nine bytes and decoded using adaptive predictive filters. citeturn33search13
〇 Star uses five audio voices for music and three for effects.	Strongly verified by first-party code.	Inkbox’s source allocates song pointers to voices 0–4 and effect pointers to voices 5–7, then runs the corresponding update paths separately. fileciteturn7file0L2-L2
Inkbox wrote a custom SPC700 sound engine and transfers it to the APU.	Verified.	The creator’s README says the engine is SPC700 assembly, compiles into a binary included in the SNES ROM and transferred to the APU, and is a snapshot of 〇 Star’s engine. fileciteturn3file0L2-L10
The playable ROM is about 129 kB.	Verified for the fetched creator-page snapshot.	Inkbox’s itch.io page lists `〇 Star SNES ROM 129 kB`. citeturn31view2
The project took two years.	Plausible but not independently verified here.	The detailed derivative article gives the two-year figure, while Hackaday verifies assembly development but does not provide that duration in the accessible text. citeturn35search6turn35search2
The generated map is exactly 192×168 tiles / ~63 kB.	Unverified game-specific detail.	Those values appear in the detailed derivative synopsis, but no accessible first-party game source was found to audit them. citeturn35search6
Only visible enemies are collision-tested.	Plausible and sensible, but game-specific implementation remains unverified.	Reported by the detailed synopsis; without the full game source or transcript, it should not be elevated to independently verified fact. citeturn35search6
Hornests created background graphics; Mouse Bite Labs designs were used for cartridge work.	Secondary-source attribution only.	These credits are reported in the detailed synopsis but were not duplicated in the first-party pages accessible in this pass. citeturn35search6

Review findings for this part

The findings come from ../../findings/ (pass 1). The script matches them to this part by source line.

ID	Severity	Evidence	Status	Location	Problem
D13-C3	critical	VIDEO VERIFY	verify	L121-125, L300, L302, L317-321	Claim: The “two most significant corrections”: the “3.58 MHz 6502” of the video and “4 MB cartridge limit” need qualification. Problem: The video makes neither claim. It never says “3.58 MHz”. It says “6502” only about the SPC700, which was “heavily inspired by the 6502” (11:47). It says “an NES cartridges 4 megabyte ROM chip” (03:08) and “My 4 megabyte cartridge ROM” (20:58). Both describe his own cartridge, not a hardware limit. The Hackaday article says “3.58 MHz Ricoh 6502-based CPU” (fetched). So the document corrects Hackaday and presents the result as a correction of the video. The ExHiROM fact itself is correct (SNESdev Memory_map, fetched).
D13-M1	major	VIDEO	open	L64, L190, L313, L323-325	Claim: “192×168 tiles” and “~63 kB” are “provisionally reported” and “unverified game-specific detail”. Problem: The video states these numbers itself: “a 192x 168 tile world”, “a 12x12 grid” of screens, “3072x 2688 pixel image”, and “fills up 63K of RAM” (06:53). The primary source confirms the secondary source. The row at L313 and the list at L325 are now out of date.
D13-M7	major	VIDEO VERIFY	verify	L266, L315, L347	Claim: Credits: “Hornests for background graphics” and “Mouse Bite Labs” are “secondary-source attribution only”. Problem: Mouse Bite Labs is in the captions: thanks “for making these SNES cartridge designs open source” (45:58). The music is by “my friend Dr. Matt” (19:07, 44:42). The document never names Dr. Matt. Hornests is not in the captions. The credit roll (47:35 to 50:10) has no captions, so Hornests stays open.
D13-m1	minor	DOC	open	L5-349	Claim: 107 `citeturn` and 16 `fileciteturn` markers. Problem: These are generation artifacts with hidden control characters. 94 lines of the document carry them. They are not citations. A reader cannot follow them.
D13-m10	minor	VIDEO	open	L224-226, L306-308	Claim: S-SMP, S-DSP, 64 KiB audio RAM, eight voices, BRR of nine bytes for 16 samples. Problem: Correct, and the video confirms it: 64K APU RAM (09:01), eight voices (10:02), “9 byt sample blocks” with a control byte and 16 nibbles (10:45 to 11:05).
D13-m9	minor	VIDEO	open	L112, L301	Claim: 128 KiB of WRAM in banks $7E to $7F. Problem: Correct, and the video confirms it: “128K of CPU RAM”, world in “bank 2” (06:31), objects planned for $7F0000 (21:18).

Review worksheet

1. Goal of this part

What does this part try to show, or help the reader decide?

2. Key claims to test

#	Claim	Evidence given (citation / data)	Verifiable?
1

3. Adversarial review

Strongest counter-argument:
Unsupported, overstated, or outdated claims:
Source quality (primary vs. blog/forum/marketing):
Omissions / what a skeptic would ask:
Internal consistency with other segments:

4. Evaluation

Does the segment achieve its goal? (Yes / Partly / No)
Confidence: (High / Medium / Low)
Required fixes: