+ *
+ * SH2 addr lines:
+ * iii. .cc. ..xx * // Internal, Cs, x
+ *
+ * sh2 map, wait/bus cycles (from docs):
+ * r w
+ * rom 0000000-0003fff 1 -
+ * sys reg 0004000-00040ff 1 1
+ * vdp reg 0004100-00041ff 5 5
+ * vdp pal 0004200-00043ff 5 5
+ * rom 2000000-23fffff 6-15
+ * dram/fb 4000000-401ffff 5-12 1-3
+ * fb ovr 4020000-403ffff
+ * sdram 6000000-603ffff 12 2 (cycles)
+ * d.a. c0000000-?