[MAME]

Gun Force
1991, Irem Corp.

PCB Layout
----------

Top board (Standard M92 Main Board)

M92-A-B   05C04170B1
|---------------------------|-----|--------------------|
|         MC3403  MC3403    |NANAO|                    |
|   064D                    |GA20 |         DSW3       |
|         MC3403  MC3403    |-----|                    |
|                             YM2151                   |
|   MC3403              YM3014                         |
|                                                      |
|J      CN6                           |-------|        |
|                      D71059C        |NEC    |        |
|A              6264                  |D71036L|        |
|                      62256   18MHz  |V33    |        |
|M                                    |-------|        |
|               6264   62256                           |
|M                           M92A-7J-.41(PAL)          |
|                                     M92A-9J-.51(PAL) |
|A                                                     |
|                               |-----|     |-----|    |
| CN4(4P)                       |NANAO|     |NANAO|    |
|                               |GA21 |     |GA22 |    |
|       M92A-3M-.11(PAL)        |-----|     |-----|    |
|                                                      |
|                       6264      6116                 |
| CN5(3P)                                              |
|       DSW2    DSW1    6264      6116      26.66666MHz|
|------------------------------------------------------|
Notes:
      V33 clock   : 9.000MHz
      GA20 clock  : 3.579545MHz (pin38)
      YM2151 clock: 3.579545MHz
      VSync       : 60Hz

      6116 : 2K x8 SRAM
      6264 : 8K x8 SRAM
      62256: 32K x8 SRAM

      CN4: Connector for 4th player controls
      CN5: Connector for 3rd player controls
      CN6: Connector for 2nd speaker (for stereo output)

      Custom chips:
                   NANAO GA20 (QFP80) - Sound chip
                   NANAO GA21 (QFP136)
                   NANAO GA22 (QFP160)



Bottom board (Game Board, differs per game)

M92-B-B   05C04171B1
|--------------------------------------------------------|
|              ROM_C0.9          ROM_001.29*  ROM_000.38 |
|                        |-----|                         |
|14.31818MHz   ROM_C1.10 |NANAO| ROM_011.30*  ROM_010.39 |
|                        |GA23 |                         |
| |----------| ROM_C2.11 |-----| ROM_021.31*  ROM_020.40 |
| |NANAO     |                                           |
| |08J27261A1| ROM_C3.12         ROM_031.32*  ROM_030.41 |
| |011       |                                           |
| |9108KK700 |                                           |
| |----------|                                           |
|                                                        |
|               GF_B-SH0-.14                             |
|                                                        |
|                                       M92_B-7H-.43(PAL)|
|                                                        |
|               6264                  GF_B-L0-C.25       |
|                                                        |
|                                     GF_B-L1-C.26       |
|               6264        62256                        |
|  M92B-2L-.7(PAL)                    GF_B-H1-C.27       |
|                           62256                        |
|  ROM_DA.8     GF_B-SL0.17           GF_B-H0-C.28       |
|                                                        |
|--------------------------------------------------------|
Notes:
      *: Unpopulated position (shown for reference for other M92 games)

      6264 : 8K x8 SRAM
      62256: 32K x8 SRAM

      Custom chips:
                   NANAO 08J27261A1 (PLCC84, encrypted V30 sound CPU, clocked at 14.31818MHz on pins 78 & 79)
                   NANAO GA23 (QFP180)

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