General Memory Map*                  Hardware Write Registers
------------------                   ------------------------
  Interrupt Enable Register
 --------------------------- FFFF
  Internal RAM
 --------------------------- FF80
  Empty but unusable for I/O
 --------------------------- FF4C
  I/O ports
 --------------------------- FF00
  Empty but unusable for I/O
 --------------------------- FEA0
  Sprite Attrib Memory (OAM)
 --------------------------- FE00
  Echo of 8kB Internal RAM
 --------------------------- E000
  8kB Internal RAM
 --------------------------- C000       -------------------------
  8kB switchable RAM bank              /      MBC1 ROM/RAM Select
 --------------------------- A000     /  ------------------------
  8kB Video RAM                      /  /     RAM Bank Select
 --------------------------- 8000 --/  /  -----------------------
  16kB switchable ROM bank   6000 ----/  /    ROM Bank Select
 --------------------------- 4000 ------/  ----------------------
  16kB ROM bank #0           2000 --------/   RAM Bank enable
 --------------------------- 0000 -------------------------------
 * NOTE: b = bit, B = byte