Bandai LZ93D50 pinout

           .---\/---.                      
        ?? |  1  52 | -- +5V                                       PPU A10 -> /  1  52 \ -> CHR A12? (=EXT PRG P31)
        ?? |  2  51 | -> PRG RAM /CS                              PPU A11 -> /  2    51 \ -> CHR A15?
PRG /CE <- |  3  50 | ?? ?                               PPU A12? (=GND) -> /  3      50 \ <- PPU /RD? (=GND)
    +5V ?? |  4  49 | ?? +5V                            PPU A13? (=GND) -> /  4        49 \ <- CPU R/W
     M2 -> |  5  48 | ?? ?                                           ? ?? /  5          48 \ <- CPU D2
CPU A13 -> |  6  47 | -> PRG A17                                  GND -- /  6            47 \ <- CPU D1
CPU A14 -> |  7  46 | -> PRG A15                                 SDA ?? /  7              46 \ <- CPU D0
 CPU A3 -> |  8  45 | -> PRG A14                            SCL INT <- /  8                45 \ <- CPU /ROMSEL
 CPU A2 -> |  9  44 | -> PRG A16                          ? (=GND) -> /  9                  44 \ <- CPU A0
 CPU A1 -> | 10  43 | <- CPU D7                          CHR /CE? <- / 10                    43 \ <- CPU A1
 CPU A0 -> | 11  42 | <- CPU D6                         CHR A10? <- / 11                      42 \ <- CPU A2
/ROMSEL -> | 12  41 | <- CPU D5                        CHR A16? <- / 12                        41 \ <- CPU A3
 CPU D0 -> | 13  40 | <> CPU D4            CHR A11? (=6264 P1) <- / 13                          40 \ ?? ?
 CPU D1 -> | 14  39 | <- CPU D3            CHR_A13? (=SCL_EXT) <- \ 14                          39 / <- CPU A14
 CPU D2 -> | 15  38 | -> /IRQ                          CHR A14? <- \ 15                        38 / <- CPU A13
    R/W -> | 16  37 | -> CIRAM A10                      CHR A17? <- \ 16                      37 / <- M2
PPU /RD -> | 17  36 | -> CHR A17                        CIRAM A10 <- \ 17                    36 / ?? ?
CHR A15 <- | 18  35 | -> CHR A14                                 ? ?? \ 18                  35 / -> PRG /CE (=EXT ROM /RD)
CHR A12 <- | 19  34 | -> CHR A13                               /IRQ <- \ 19                34 / ?? ?
PPU A10 -> | 20  33 | -> CHR A11                              CPU D3 -> \ 20              33 / -- GND
PPU A11 -> | 21  32 | -> CHR A16                               CPU D4 -> \ 21            32 / -- VCC
PPU A12 -> | 22  31 | -> CHR A10                                CPU D5 -> \ 22          31 / -> /$6000-$7FFF (=74368's/OE)
PPU A13 -> | 23  30 | -> CHR /CE                                 CPU D6 -> \ 23        30 / ?? ?
    GND -- | 24  29 | <- **                                       CPU D7 -> \ 24      29 / ?? ?
      ? ?? | 25  28 | -> I²C SCL                                  PRG A16 <- \ 25    28 / -> PRG A17
    GND -- | 26  27 | <> I²C SDA                                   PRG A14 <- \ 26  27 / -> PRG A15
           '--------'                         
Bandai LZ93D50: 52-pin shrink PDIP                                 Bandai LZ93D50P: QFP52 0.65mm pitch
(Canonically iNES Mapper 159)                                   (Canonically iNES Mapper 157)                                      
                                                         
** Grounded on BA-JUMP2. Floating on other games.         * This chip is used only in Datach Joint System Adapter with
   Seems likely to be an enable for reading I²C from        non-canonical connections (marked as =...)
   $6000-$7fff (internal pullup, normally floating)       * Behaviour of pins ending with "?" is not confirmed, but it
                                                            is suggested by their location identical to PDIP version 

Bandai's variants of the LZ93D50 are almost as bad as MMC1.

BA-JUMP2: supports PRG RAM instead of I²C, replaces banked CHR-ROM with unbanked CHR-RAM, and increases PRG max to 512KiB:

PPU /RD -> | 17  36 | -> n/c
    n/c <- | 18  35 | -> n/c
    n/c <- | 19  34 | -> n/c
PPU A10 -> | 20  33 | -> n/c
PPU A11 -> | 21  32 | -> n/c
    GND -> | 22  31 | -> PRG A18
    GND -> | 23  30 | -> n/c
    GND -- | 24  29 | <- GND
      ? ?? | 25  28 | -> PRG RAM +CS
    GND -- | 26  27 | <> n/c
           '--------'

Datach Joint ROM System: Two separate I²C clocks, replaces banked CHR-ROM with unbanked CHR-RAM, and external barcode reader.

This IC is actually a 52-pin QFP, with a slightly different pin order from the PDIP instantiation. The pertinent changes:

• I²C SCL is only for the internal EEPROM
• CHR A13 is External I²C SCL
• WRAM /CS drives a tristateable buffer that connects barcode data to CPU D3.

See also:

• http://seesaawiki.jp/famicomcartridge/d/Bandai%20Datach
• http://seesaawiki.jp/famicomcartridge/d/Bandai%20LZ93D50%20standard