[MAME]

Sega NAOMI Mainboard
Sega, 1998-2005

PCB Layout
----------
837-13544-01
171-7772F
837-13707 (sticker)
(C) SEGA 1999
|---------------------------------------------------|
|    CN1                           CN3              |
|PC910  62256   EPF8452AQC160-3                     |
|    BATTERY EPC1064   JP4  3771  93C46             |
|A179B    315-6188.IC31     3771                3773|
|ADM485  BIOS.IC27   5264165            5264165     |
|                    5264165  |-----|   5264165     |
|    CN3                      |POWER|               |
|                             |VR2  | 33.3333MHZ    |
|CN26                         |-----|          27MHZ|
|                                         CY2308SC-3|
|        KM416S4030      |------|     HY57V161610   |
|                        | SH4  |     HY57V161610   |
| C844G        315-6232  |      |             32MHZ |
|            33.8688MHZ  |------|     HY57V161610   |
|                         xMHz        HY57V161610   |
|      PCM1725    JP1                    62256      |
|                     HY57V161610                   |
|                          HY57V161610              |
|              315-6145                             |
|CN25                CY2308SC-1          315-6146   |
|          LED1                              93C46  |
|          LED2                     14.7456MHZ      |
|---------------------------------------------------|
Notes:
      CN1/2/3         - Connectors for ROM cart
      CN25/26         - Connectors for filter board
      EPF8452AQC160-3 - Altera FLEX EPF8452AQC160-3 FPGA (QFP160)
      315-6188.IC31   - Altera EPC1064 (DIP8)
      JP1             - set to 2-3. Alt setting is 1-2
      JP4             - set to 2-3. Alt setting is 1-2
      93C46           - 128 bytes EEPROM
      A179B 96K       - ?, made by TI
      ADM485          - Analog Devices ADM485
      BIOS.IC27       - 27C160 EPROM
      5264165         - Hitachi 5264165FTTA60 (video RAM)
      HY57V161610     - Hyundai 57V161610DTC-8 (main program RAM)
      CY2308SC-3      - Clock generator IC
      KM416S4030      - Samsung KM416S4030 16MBit SDRAM (sound related RAM?)
      315-6232        - Sega Custom IC (QFP100)
      315-6145        - Sega Custom IC (QFP56)
      315-6146        - Sega Custom IC (QFP176)
      C844G           - ? (SOIC14)
      62256           - 32kx8 SRAM
      PCM1725         - Burr-Brown PCM1725
      xMHz            - Small round XTAL (possibly 32.768kHz for a clock?)
      SH4             - Hitachi SH4 CPU (BGAxxx, with heatsink and fan)
      POWERVR2        - POWERVR2 video generator (BGAxxx, with heatsink)

Filter Board
------------
839-1069
|----------------------------------------------------|
|SW2 SW1   DIPSW   CN5                      CN12 CN10|
|                                                    |
|                                                    |
|           DIN1                     DIN2            |
|                                                    |
|               CNTX  CNRX                           |
| CN9    CN8                                         |
|    CN7     CN6           CN4       CN3    CN2   CN1|
|----------------------------------------------------|
Notes:
      CN1/CN2   - Power input
      CN3       - HD15 (i.e. VGA connector) RGB Video Output @ 15kHz or 31.5kHz
      CN4       - RCA Audio Output connectors
      CN5       - USB connector (connection to I/O board)
      CN6       - 10 pin connector labelled 'MAPLE 0-1'
      CN7       - 11 pin connector labelled 'MAPLE 2-3'
      CN8       - RS422 connector
      CN9       - Midi connector
      CNTX/CNRX - Network connectors
      DIN1/DIN2 - Connectors joining to mainboard CN25/26
      SW1       - Test Switch
      SW2       - Service Switch
      DIPSW     - 4-position DIP switch block
      CN10      - 12 volt output for internal case exhaust fan
      CN11      - RGB connector (not populated)
      CN12      - 5 volt output connector

-


[Dec/12/2002]

This file is the naomi Bios for export system version D it is a ST 27c160 16Mbit/16 bit.
There are 4 different bios region (Japan, Usa, Export and Australia) everyone with their
own  EPR number.
There are different revision for each reagion, but all with the same change, i think.
From ver. A to D the bios allows ONLY game on cart.
From D it can handle GD-Rom board.
And from F or G (i have to check it) it can handle the network GD-Rom board.
Naomi1 and Naomi2 bios are different :)
F355 has it own bios and different JVS I/O board.
Virtua tennis2 (GD-Rom) work on japanese bios AND on export with title change
(power smash2/virtua tennis2) other game like Gundam federation
VS Zeon DX (??) GD-Rom work ONLY with american bios
(i don't have Australia one to try it, i try only jap/exp and usa).
F355 can use maple bus to "drive" memory card other game may use this feature.
The I/O board is connected to the main board with a USB link. The JVS I/O has
it own cpu that handle all input (digital and analog ones) than it send it via USB.
The cpu is a Toshiba microcontroller with embedded rom.
If you need some help ask :)
I can dump a VS3 program rom if yuo need it, it's a pre-bugfix version, some machine
have a bug that delete bookkeeping after 31/may/2001 if I remember well...

Sorry for my poor English but i understand it very well, but i can't speak and write
it at the same level.

-

