
========================
=  Mapper 071          =
========================


Example Games:
--------------------------
MiG 29 - Soviet Fighter
Fire Hawk
The Fantastic Adventures of Dizzy
Bee 52


Notes:
--------------------------
This mapper covers several Camerica/Codemasters boards.  One in paticular that needs to be noted is the board
used by Fire Hawk -- which has mapper controlled 1-screen mirroring.  On other boards, mirroring is
hardwired!  This is yet another one of those terrific mapper number incompatibilities.

Some of these games are EXTREMELY DIFFICULT to emulate.  Not because the mapper is complicated (it's actually
very simple), but because the games are picky about timing and use some seldom used aspects of the NES.

In paticular:
- Bee 52 uses the sprite overflow flag ($2002.5)
- MiG 29 uses DMC IRQs, and is VERY PICKY about their timing.  If your DMC IRQ timing isn't spot on (or at
least really freaking close), this game will glitch like hell.


This mapper also involves a custom lockout defeat circuit which is mostly unimportant for emulation purposes.
Details will not be mentioned here, but are outlined in Kevtris' Camerica Mappers documentation.

Fire Hawk does some strange timing code when changing the mirroring mode.  It is unknown whether or not any
special timing is required.


Registers:
--------------------------

  $8000-9FFF:  [...M ....]  Mirroring (for Fire Hawk only!)
     0 = 1ScA
     1 = 1ScB

  $C000-FFFF:  PRG Select (16k @ $8000)


PRG Setup:
--------------------------

      $8000   $A000   $C000   $E000  
    +---------------+---------------+
    |     $C000     |     { -1}     |
    +---------------+---------------+
