diff --git a/src/mame/drivers/namcos23.c b/src/mame/drivers/namcos23.c
index 2c65de148dd..52de99c7dc8 100644
--- a/src/mame/drivers/namcos23.c
+++ b/src/mame/drivers/namcos23.c
@@ -23,9 +23,7 @@
     TODO:
     - Palette is not right.
 
-    - H8/3002 now communicates with the H8/3334 on the I/O board, but it's not reliable yet.
-
-    - Hook up actual inputs (?) via the 2 serial latches at d00004 and d00006.
+    - Hook up gun inputs (?) via the 2 serial latches at d00004 and d00006.
       Works like this: write to d00004, then read d00004 12 times.  Ditto at
       d00006.  This gives 24 bits of inputs (?) from the I/O board (?) or guns (?)
 
@@ -945,6 +943,11 @@ static VIDEO_UPDATE( ss23 )
 	return 0;
 }
 
+static READ32_HANDLER( s23_txtchar_r )
+{
+	return namcos23_charram[offset];
+}
+
 static WRITE32_HANDLER( s23_txtchar_w )
 {
 	COMBINE_DATA(&namcos23_charram[offset]);
@@ -1058,21 +1061,22 @@ static READ32_HANDLER( gorgon_magic_r )
 
 static ADDRESS_MAP_START( gorgon_map, ADDRESS_SPACE_PROGRAM, 32 )
 	AM_RANGE(0x00000000, 0x003fffff) AM_RAM
-	AM_RANGE(0x01000000, 0x0100003f) AM_READ( gorgon_magic_r )
+	AM_RANGE(0x01000000, 0x010000ff) AM_READ( gorgon_magic_r )
 	AM_RANGE(0x02000000, 0x02000003) AM_READ( gorgon_vbl_r )
 	AM_RANGE(0x04400000, 0x0440ffff) AM_RAM AM_BASE(&namcos23_shared_ram)
 
 	AM_RANGE(0x04c3ff08, 0x04c3ff0b) AM_WRITE( s23_mcuen_w )
 	AM_RANGE(0x04c3ff0c, 0x04c3ff0f) AM_RAM				// 3d FIFO
 
-	AM_RANGE(0x06110000, 0x0613ffff) AM_READ(namcos23_paletteram_r) AM_WRITE(namcos23_paletteram_w) AM_BASE_GENERIC(paletteram)
+	AM_RANGE(0x06108000, 0x061087ff) AM_RAM		// GAMMA (C404-3S)
+	AM_RANGE(0x06110000, 0x0613ffff) AM_READWRITE(namcos23_paletteram_r, namcos23_paletteram_w) AM_BASE_GENERIC(paletteram)
+	AM_RANGE(0x06400000, 0x06403fff) AM_READWRITE( s23_txtchar_r, s23_txtchar_w ) AM_BASE(&namcos23_charram)	// text layer characters
+	AM_RANGE(0x06404000, 0x0641dfff) AM_RAM
+	AM_RANGE(0x0641e000, 0x0641ffff) AM_READWRITE(namcos23_textram_r, namcos23_textram_w) AM_BASE(&namcos23_textram)
 
-	AM_RANGE(0x06400000, 0x06403fff) AM_WRITE( s23_txtchar_w ) AM_BASE(&namcos23_charram)	// text layer characters
-	AM_RANGE(0x0641e000, 0x0641ffff) AM_READ(namcos23_textram_r) AM_WRITE(namcos23_textram_w) AM_BASE(&namcos23_textram)
+	AM_RANGE(0x08000000, 0x087fffff) AM_ROM AM_REGION("data", 0)	// data ROMs
 
-	AM_RANGE(0x08000000, 0x087fffff) AM_ROM AM_REGION("data", 0)	// data ROMs?
-
-	AM_RANGE(0x0d000000, 0x0d000007) AM_READ(sysctl_stat_r)
+	AM_RANGE(0x0d000000, 0x0d000007) AM_READ(sysctl_stat_r)	// write for LEDs
 	AM_RANGE(0x0fc00000, 0x0fffffff) AM_WRITENOP AM_ROM AM_REGION("user1", 0)
 	AM_RANGE(0x1fc00000, 0x1fffffff) AM_WRITENOP AM_ROM AM_REGION("user1", 0)
 ADDRESS_MAP_END
@@ -1083,12 +1087,11 @@ static ADDRESS_MAP_START( ss23_map, ADDRESS_SPACE_PROGRAM, 32 )
 	AM_RANGE(0x04400000, 0x0440ffff) AM_RAM AM_BASE(&namcos23_shared_ram)
 	AM_RANGE(0x04c3ff08, 0x04c3ff0b) AM_WRITE( s23_mcuen_w )
 	AM_RANGE(0x04c3ff0c, 0x04c3ff0f) AM_RAM				// 3d FIFO
-	AM_RANGE(0x06800000, 0x06800fff) AM_RAM 			// text layer palette
-	AM_RANGE(0x06800000, 0x06807fff) AM_WRITE( s23_txtchar_w ) AM_BASE(&namcos23_charram)	// text layer characters
+	AM_RANGE(0x06800000, 0x06807fff) AM_READWRITE( s23_txtchar_r, s23_txtchar_w ) AM_BASE(&namcos23_charram)	// text layer characters (shown as CGRAM in POST)
 	AM_RANGE(0x06804000, 0x0681dfff) AM_RAM
-	AM_RANGE(0x0681e000, 0x0681ffff) AM_READ(namcos23_textram_r) AM_WRITE(namcos23_textram_w) AM_BASE(&namcos23_textram)
-	AM_RANGE(0x06a08000, 0x06a0ffff) AM_RAM	//gamma?
-	AM_RANGE(0x06a10000, 0x06a3ffff) AM_READ(namcos23_paletteram_r) AM_WRITE(namcos23_paletteram_w) AM_BASE_GENERIC(paletteram)
+	AM_RANGE(0x0681e000, 0x0681ffff) AM_READWRITE(namcos23_textram_r, namcos23_textram_w) AM_BASE(&namcos23_textram)
+	AM_RANGE(0x06a08000, 0x06a0ffff) AM_RAM	// GAMMA (C404)
+	AM_RANGE(0x06a10000, 0x06a3ffff) AM_READWRITE(namcos23_paletteram_r, namcos23_paletteram_w) AM_BASE_GENERIC(paletteram)
 	AM_RANGE(0x06820008, 0x0682000f) AM_READ( ss23_vstat_r )	// vblank status?
 	AM_RANGE(0x08000000, 0x08017fff) AM_RAM
 	AM_RANGE(0x0d000000, 0x0d000007) AM_READ(sysctl_stat_r) AM_WRITENOP
@@ -1576,7 +1579,7 @@ ROM_START( rapidrvr )
 	ROM_REGION( 0x80000, "audiocpu", 0 )	/* Hitachi H8/3002 MCU code */
 	ROM_LOAD16_WORD_SWAP( "rd3verc.ic3",  0x000000, 0x080000, CRC(6e26fbaf) SHA1(4ab6637d22f0d26f7e1d10e9c80059c56f64303d) )
 
-	ROM_REGION32_BE( 0x800000, "data", 0 )	/* sprite? tilemap? tiles */
+	ROM_REGION32_BE( 0x800000, "data", 0 )	/* data */
         ROM_LOAD16_BYTE( "rd1mtal.1j",   0x000001, 0x400000, CRC(8f0efa86) SHA1(9953461c258f2a96be275a7b18d6518ddfac3860) )
         ROM_LOAD16_BYTE( "rd1mtah.3j",   0x000000, 0x400000, CRC(d8fa0f3d) SHA1(0d5bdb3a2e7be1dffe11b74baa2c10bfe011ae92) )
 
@@ -1635,7 +1638,7 @@ ROM_START( finlflng )
 	ROM_REGION( 0x80000, "audiocpu", 0 )	/* Hitachi H8/3002 MCU code */
         ROM_LOAD16_WORD_SWAP( "ff2vera.ic3",  0x000000, 0x080000, CRC(ab681078) SHA1(ec8367404458a54893ab6bea29c8a2ba3272b816) )
 
-	ROM_REGION32_BE( 0x800000, "data", 0 )	/* sprite? tilemap? tiles */
+	ROM_REGION32_BE( 0x800000, "data", 0 )	/* data */
         ROM_LOAD16_BYTE( "ff2mtal.1j",   0x000001, 0x400000, CRC(ed1a5bf2) SHA1(bd05388a125a0201a41af95fb2aa5fe1c8b0f270) )
         ROM_LOAD16_BYTE( "ff2mtah.3j",   0x000000, 0x400000, CRC(161003cd) SHA1(04409333a4776b17700fc6d1aa06a39560132e03) )