INES Mapper 245

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"Mapper 245 uses bit 2 of CHR Register 0 to select which 512KB bank of PRG ROM is seen. This increases the maximum PRG size up to 1024K. CHR RAM is not bankable, but the top bit of $8000 will still switch the left and right pattern tables."

 Here are Disch's original notes:  
 ========================
 =  Mapper 245          =
 ========================
 
 
 Example Games:
 --------------------------
 Chu Han Zheng Ba - The War Between Chu & Han
 Xing Ji Wu Shi - Super Fighter
 Yin He Shi Dai
 Yong Zhe Dou e Long - Dragon Quest VII (As)
 Dong Fang de Chuan Shuo - The Hyrule Fantasy
 
 
 Notes:
 ---------------------------
 Another ?Chinese? MMC3 clone.  Very similar to your typical MMC3.  For MMC3 info, see mapper 004.
 
 Register layout is identical to a typical MMC3.
 
 
 
 CHR Setup:
 ---------------------------
 
 CHR-RAM is not swappable.  When there is no CHR-ROM present, 8k CHR-RAM is fixed.  However the CHR Mode bit
 ($8000.7) can still "flip" the left/right pattern tables.
 
 Example:
 
                     $0000   $0400   $0800   $0C00   $1000   $1400   $1800   $1C00 
                   +-------------------------------+-------------------------------+
 CHR-RAM, Mode 0:  |             { 0 }             |             { 1 }             |
                   +-------------------------------+-------------------------------+
 CHR-RAM, Mode 1:  |             { 1 }             |             { 0 }             |
                   +---------------------------------------------------------------+
 CHR-ROM:          |                          Typical MMC3                         |
                   +---------------------------------------------------------------+
 
 
 PRG Setup:
 ---------------------------
 
 PRG Setup is the same as a normal MMC3, although there's a PRG-AND of $3F, and games select a 512k Block with
 bit 1 of R:0.  Pretty simple really:
 
    R:0:  [.... ..P.]
 
   'P'    PRG-AND    PRG-OR
  --------------------------
    0       $3F        $00
    1       $3F        $40
 
 
 R:0 remains the normal MMC3 CHR reg, as well.  Although the game that uses it as a PRG block selector ("DQ7")
 uses CHR-RAM, so it is normally ignored.