View source for Sachen SA8259A pinout

[[Category:Pinouts]][[Sachen 8259|Sachen SA8259A]]: 28-pin 0.6" DIP

Most of Sachen's mapper ICs have names that collide with other well-known ICs, presumably as an initial round of indirection to confuse would-be mass copiers. The 8259A is canonically the original IBM PC's [[wikipedia:Programmable Interrupt Controller|Programmable Interrupt Controller]].

               .---\/---.              
    PRG A15 <- | 01  28 | -- Vcc
  CIRAM A10 <- | 02  27 | -> r42
    PPU A11 -> | 03  26 | <- CPU A8 (+CE)
    PPU A13 -> | 04  25 | -> rX0
    PPU /RD -> | 05  24 | <- R/W
          ? ?? | 06  23 | <- M2
    PRG A16 <- | 07  22 | <- PPU A12
    CPU A14 -> | 08  21 | <- PPU A10
    CPU  A0 -> | 09  20 | <- /ROMSEL
        rX1 <- | 10  19 | -> r41
    CPU  D0 -> | 11  18 | <- CPU D2
    CPU  D1 -> | 12  17 | -> r60
    PRG A17 <- | 13  16 | -> rX2
        GND -- | 14  15 | -> r40
               '--------'

The exact connectivity of the pins labelled r?? depends on the
corresponding mapper number or name allocated.

{| class='datatable'
! pin \ mapper !! [[iNES Mapper 137|137]] !! 138 !! 139 !! 141
|-
| rX0 || CHR A10 || CHR A11 || CHR A13 || CHR A12
|-			 			 								        
| rX1 || CHR A11 || CHR A12 || CHR A14 || CHR A13
|-			 			 							        
| rX2 || CHR A12 || CHR A13 || CHR A15 || CHR A14
|-											        
| r40 || CHR A14¹ || CHR A14 || CHR A16 || CHR A15
|-											        
| r41 || CHR A14¹ || CHR A15 || CHR A17 || CHR A16
|-
| r42 || CHR A14¹ || CHR A16 || CHR A18 || CHR A17
|-
| r60 || CHR A13¹ || n/c || n/c || n/c
|}

¹: r40, r41, r42, and r60 go through a 74LS253 dual 4 to 1 multiplexer and a 74LS257 quad 2 to 1 multiplexer to produce 4x1+4F CHR banking

Reference: Cah4e3 ( http://cah4e3.shedevr.org.ru/%5Blst%5D-sachen-mappers.txt )