From 9c84b7990afaf3eb84ba88092ff3bb745376dbbf Mon Sep 17 00:00:00 2001
From: Abdessamad Derraz <3028866+Abdess@users.noreply.github.com>
Date: Tue, 6 Oct 2026 08:52:26 +0200
Subject: [PATCH] fix: give np2kai scsi.rom a read ceiling, not a size

---
 emulators/np2kai.yml             | 10 ++++++----
 tests/test_game_data_homonyms.py | 15 +++++++++++++++
 2 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/emulators/np2kai.yml b/emulators/np2kai.yml
index f996af92..dd261bd2 100644
--- a/emulators/np2kai.yml
+++ b/emulators/np2kai.yml
@@ -151,16 +151,18 @@ files:
     source_ref: "cbus/ideio.c:1928-1930, cbus/ideio.c:1944-1981"
 
   # -- SCSI BIOS ROM --
-  # Loaded by scsiio.c:219. 16 KB (0x4000). Falls back to scsibios[] stub.
+  # Read into a 0x4000 buffer; any non-empty read is kept. Falls back to the
+  # scsibios[] stub.
   - name: "scsi.rom"
     path: "np2kai/scsi.rom"
-    size: 16384
+    max_size: 16384
     required: false
     hle_fallback: true
     note: >
-      SCSI controller BIOS ROM (16 KB). The core includes a built-in
+      SCSI controller BIOS ROM, up to 16 KB: the full-size test is commented
+      out and a shorter file is used as read. The core includes a built-in
       SCSI BIOS stub as fallback.
-    source_ref: "cbus/scsiio.c:214-231"
+    source_ref: "cbus/scsiio.c:720-732"
 
   # -- SASI BIOS ROM --
   # Loaded by sasiio.c:455. 4 KB (0x1000). Falls back to sasibios[] stub.
diff --git a/tests/test_game_data_homonyms.py b/tests/test_game_data_homonyms.py
index 6f6113ac..a54a95fa 100644
--- a/tests/test_game_data_homonyms.py
+++ b/tests/test_game_data_homonyms.py
@@ -314,5 +314,20 @@ class SwitchKeysAreTheNewestSet(unittest.TestCase):
                 self.assertEqual(newest(REPO_ROOT / path), best)
 
 
+class Pc98ScsiBiosIsNotTheAppleCard(unittest.TestCase):
+    """np2kai declared an exact 16 KB its loader never requires; the Apple II
+    SCSI card ROM of that size won the name tie over the PC-98 BIOS."""
+
+    def test_np2kai_resolves_the_pc98_rom(self):
+        db_path = REPO_ROOT / "database.json"
+        if not db_path.exists():
+            self.skipTest("no database.json")
+        db = load_database(str(db_path))
+        profile = load_emulator_profiles(str(REPO_ROOT / "emulators"))["np2kai"]
+        entry = next(e for e in profile["files"] if e["name"] == "scsi.rom")
+        path, _status = resolve_local_file(entry, db, dest_hint=entry["path"])
+        self.assertIn("PC-98", path or "")
+
+
 if __name__ == "__main__":
     unittest.main()