Commit the Indy IP24 PROM dumps

Preserve the four MAME indy_4610 ROM images alongside the existing
SHA-1 manifest and analysis. The zip and generated ELF wrapper remain
ignored.

.gitignore

@@ -1,5 +1,5 @@
-# SGI firmware dumps and generated wrappers (copyrighted, fetch on demand)
-roms/*.bin
+# Downloads and generated wrappers. The four checked-in .bin dumps are the
+# archived ROM set; the zip is only an acquisition artifact.
 roms/*.zip
 roms/*.elf
 

README.md

@@ -32,17 +32,20 @@ table, boot flow and function anchors.
 See [docs/rom-map.json](docs/rom-map.json) for the machine-readable layout and
 [docs/procedure-index.csv](docs/procedure-index.csv) for every function start.
 
-## ROM files are not committed
+## ROM files
 
-The PROM dumps are copyrighted SGI firmware. `roms/*.bin`, the MAME zip and the
-generated ELF wrapper are ignored by git. Fetch and verify them with:
+The four PROM dumps from the MAME 0.236 `indy_4610` set are committed under
+`roms/` for preservation, together with `roms/SHA1SUMS`. The MAME zip and the
+generated ELF wrapper stay ignored.
+
+The dumps can be re-fetched and verified with:
 
 ```bash
 ./tools/fetch-roms.sh
 ```
 
-The fetch script downloads the MAME 0.236 `indy_4610` set and checks every SHA-1
-against MAME's `src/mame/sgi/indy_indigo2.cpp`.
+The fetch script downloads the `indy_4610` set and checks every SHA-1 against
+MAME's `src/mame/sgi/indy_indigo2.cpp`.
 
 ## Reproduce the analysis
 

roms/README.md

@@ -1,8 +1,11 @@
 # ROM dumps
 
-The binaries themselves are not committed; they are copyrighted SGI firmware.
-Run `../tools/fetch-roms.sh` to download the MAME 0.236 `indy_4610` set and
-verify it against `SHA1SUMS`.
+These four dumps from the MAME 0.236 `indy_4610` set are committed here for
+preservation. They are copyrighted SGI firmware; check your local rules before
+redistributing them.
+
+Verify them against `SHA1SUMS`, or re-fetch the set with
+`../tools/fetch-roms.sh`.
 
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