diff --git a/src/gamegear.c b/src/gamegear.c
index ad9f553..3ecc0dd 100644
--- a/src/gamegear.c
+++ b/src/gamegear.c
@@ -125,10 +125,10 @@ const char* gamegear_get_exception(GameGear *gg)
                     SET_EXC("CPU not powered")
                     break;
                 case Z80_EXC_UNIMPLEMENTED_OPCODE:
-                    SET_EXC("Unimplemented opcode: 0x%02X", gg->cpu.exc_data)
+                    SET_EXC("unimplemented opcode: 0x%02X", gg->cpu.exc_data)
                     break;
                 default:
-                    SET_EXC("Unknown exception")
+                    SET_EXC("unknown exception")
                     break;
             }
         } else {
diff --git a/src/rom.c b/src/rom.c
index c7d8667..d4b9f89 100644
--- a/src/rom.c
+++ b/src/rom.c
@@ -105,7 +105,8 @@ static bool parse_header(ROM *rom, const uint8_t *header)
     else
         DEBUG("  - checksum:      0x%04X (invalid, expected 0x%04X)",
               rom->reported_checksum, rom->expected_checksum)
-    DEBUG("  - product code:  %u", rom->product_code)
+    DEBUG("  - product code:  %u (%s)", rom->product_code,
+          rom_product(rom) ? rom_product(rom) : "unknown")
     DEBUG("  - version:       %u", rom->version)
     DEBUG("  - region code:   %u (%s)", rom->region_code,
           rom_region(rom) ? rom_region(rom) : "unknown")
@@ -227,6 +228,18 @@ void rom_close(ROM *rom)
 }
 
 /*
+    Return a string explanation of this ROM's product code.
+
+    NULL is returned if the product code is not known.
+*/
+const char* rom_product(const ROM *rom)
+{
+    // TODO
+
+    return NULL;
+}
+
+/*
     Return the region this ROM was intended for, based on header information.
 
     NULL is returned if the region code is invalid.
diff --git a/src/rom.h b/src/rom.h
index 15de218..d5a1c33 100644
--- a/src/rom.h
+++ b/src/rom.h
@@ -41,4 +41,5 @@ typedef struct {
 
 const char* rom_open(ROM**, const char*);
 void rom_close(ROM*);
+const char* rom_product(const ROM*);
 const char* rom_region(const ROM*);