Cartridge Connector LoROM:

                         ---+---
                    GND |05 | 36| GND
                    A11 |06 | 37| A12
                    A10 |07 | 38| A13
                     A9 |08 | 39| A14
                     A8 |09 | 40| NC or to MAD-1 Decoder pin #15
                     A7 |10 | 41| A15
                     A6 |11 | 42| A16
                     A5 |12 | 43| A17
                     A4 |13 | 44| A18
                     A3 |14 | 45| A19
                     A2 |15 | 46| A20 
                     A1 |16 | 47| A21
                     A0 |17 | 48| A22
                   /IRQ |18 | 49| /OE
                     D0 |19 | 50| D4
                     D1 |20 | 51| D5
                     D2 |21 | 52| D6
                     D3 |22 | 53| D7
                    /CE |23 | 54| /WE
             Pin 1 D413 |24 | 55| Pin 2 D413
             Pin 7 D413 |25 | 56| Pin 6 D413
                 RAM /E |26 | 57| NC
                    VCC |27 | 58| VCC
                         ---+---

Pin #23 -> ROM /CE and RAM /OE (connected together)
Pin #49 -> ROM /OE
Pin #54 -> RAM /WE
Pin #40 is NC when cart have 74LS139 or don't have any decoder,
otherwise is connect to MAD-1 pin #15

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