--- /dev/null
+#VRCIV A0,A1 reversed + A1 invert + Address BUS 6²ó¥·¥Õ¥È
+#IV - CPU
+#A0 = A7
+#A1 ^ A6
+#mapper 21 ¤Ï VRC4A ¤È¤«¤Ö¤ë¤¬¥ì¥¸¥¹¥¿¥¢¥É¥ì¥¹¤¬°Û¤Ê¤ë(Ê̤ΥޥåѤˤ·¤Ê¤¤¤Î??)
+#RC857 ¤¬¤ó¤Ð¤ì¥´¥¨¥â¥ó³°ÅÁ2 Å·²¼¤ÎºâÊõ
+MAPPER 21
+CPU_ROMSIZE 0x40000
+PPU_ROMSIZE 0x40000
+#$8000 bit2:0 $a000 switch $8000-$9fff
+#$8000 bit2:1 $a000 switch $c000-$dfff
+DUMP_START
+CPU_WRITE $9080 $00
+STEP_START i 0 0x1e 2
+ CPU_WRITE $8000 i + 0
+ CPU_WRITE $a000 i + 1
+ CPU_READ $8000 0x4000
+STEP_END
+CPU_WRITE $9080 $02
+CPU_WRITE $8000 $1e
+CPU_READ $c000 0x4000
+
+STEP_START up 0 0x100 0x10
+ STEP_START v 0 0x10 8
+ CPU_WRITE $b040 up >> 4
+ CPU_WRITE $b000 v | 0
+ CPU_WRITE $b0c0 up >> 4
+ CPU_WRITE $b080 v | 1
+ CPU_WRITE $c040 up >> 4
+ CPU_WRITE $c000 v | 2
+ CPU_WRITE $c0c0 up >> 4
+ CPU_WRITE $c080 v | 3
+ CPU_WRITE $d040 up >> 4
+ CPU_WRITE $d000 v | 4
+ CPU_WRITE $d0c0 up >> 4
+ CPU_WRITE $d080 v | 5
+ CPU_WRITE $e040 up >> 4
+ CPU_WRITE $e000 v | 6
+ CPU_WRITE $e0c0 up >> 4
+ CPU_WRITE $e080 v | 7
+ PPU_READ 0 0x2000
+ STEP_END
+STEP_END
+DUMP_END