[Apr/04/2004]

GNET Motherboard
Taito, 1998

This is the Taito GNET System. It comprises the following main parts....
- Sony ZN-2 Motherboard (Main CPU/GPU/SPU, RAM, BIOS, EEPROM & peripheral interfaces)
- Taito FC PCB (Sound hardware & FLASHROMs for storage of PCMCIA cart contents)
- Taito CD PCB (PCMCIA cart interface)

Also available are...
- Optional Communication Interface PCB
- Optional Save PCB

On power-up, the system checks for a PCMCIA cart. If the cart matches the contents of the FLASHRAMs, 
the game boots immediately with no delay. If the cart doesn't match, it re-flashes the FLASHROMs with _some_ 
of the information contained in the cart, which takes approximately 2-3 minutes. The game then boots up.

If no cart is present on power-up, the Taito GNET logo is displayed, then a message 'SYSTEM ERROR'


PCB Layouts
-----------

ZN-2  COH-3002T
|--------------------------------------------------------|
|  LA4705             |---------------------------|      |
|                     |---------------------------|      |
|    AKM_AK4310VM      AT28C16                           |
|  VOL                                                   |
|       S301           COH3002T.353                      |
|                                                        |
|                                                        |
|J                                                       |
|                                                        |
|A              814260    CXD2925Q     EPM7064           |
|                                                        |
|M                                                       |
|                                                        |
|M                                                       |
|            S551    KM4132G271BQ-8                      |
|A                                                       |
|                                CXD8654Q    CXD8661R    |
|                    KM4132G271BQ-8                      |
|CN505  CN506                   53.693MHz    100MHz      |
|            CAT702                                      |
|                                                        |
|CN504  CN503                                            |
|                                                        |
|            MC44200FT                                   |
|  NEC_78081G503        KM416V1204BT-L5  KM416V1204BT-L5 |
|                                                        |
|CN651  CN652                 *                 *        |
|                CN654                                   |
|--------------------------------------------------------|
Notes:
      CN506 - Connector for optional 3rd player controls
      CN505 - Connector for optional 4th player controls
      CN503 - Connector for optional 15kHz external video output (R,G,B,Sync, GND)
      CN504 - Connector for optional 2nd speaker (for stereo output)
      CN652 - Connector for optional trackball
      CN651 - Connector for optional analog controls
      CN654 - Connector for optional memory card
      S301  - Slide switch for stereo or mono sound output
      S551  - Dip switch (4 position, defaults all OFF)
      
      COH3002T.353   - GNET BIOS 4MBit MaskROM type M534002 (SOP40)
      AT28C16        - Atmel AT28C16 2K x8 EEPROM
      814260-70      - 256K x16 (4MBit) DRAM 
      KM4132G271BQ-8 - 128K x 32Bit x 2 Banks SGRAM
      KM416V1204BT-L5- 1M x16 EDO DRAM
      EPM7064        - Altera EPM7064QC100 CPLD (QFP100)
      CAT702         - Protection chip labelled 'TT10' (DIP20)
      *              - Unpopulated position for additional KM416V1204BT-L5 RAMs


FC PCB  K91X0721B  M43X0337B
|--------------------------------------------|
|   |---------------------------|            |
|   |---------------------------|            |
| NJM2100  NJM2100                           |
| MB87078                                    |
| *MB3773     XC95108         DIP40   CAT702 |
| *ADM708AR                                  |
| *UPD6379GR                                 |
|             FLASH16                        |
|                                            |
| DIP24                                      |
|                  *RF5C296                  |
| -------CD-PCB------- _                     |
| |                   | |                    |
| |                   | |                    |
| |                   | |                    |
| |                   | |                    |
| |                   | |                    |
| |                   | |                    |
| |                   | |                    |
| |                   |-|                    |
| --------------------                       |
|            M66220FP      FLASH16  FLASH16  |
|      FLASH4                  FLASH16       |
|*LC321664                                   |
| TMS57002DPHA                *ZSG-2         |
|           LH52B256      25MHz              |
|   MN1020012A                               |
|--------------------------------------------|
Notes:
      DIP40        - Unpopulated socket for 8MBit DIP40 EPROM type AM27C800
      DIP24        - Unpopulated position for FM1208 DIP24 IC
      FLASH16      - Intel TE28F160 16MBit FLASHROM (TSOP56)
      FLASH4       - Intel E28F400 4MBit FLASHROM (TSOP48)
      LH52B256     - Sharp 32K x8 SRAM (SOP28)
      LC321664     - Sanyo 64K x16 EDO DRAM (SOP40)
      XC95108      - XILINX XC95108 CPLD labelled 'E65-01' (QFP100)
      MN1020012A   - Panasonic MN1020012A Sound CPU (QFP128)
      ZSG-2        - Zoom Corp ZSG-2 sound DSP (QFP100)
      TMS57002DPHA - Texas Instruments TMS57002DPHA sound DSP (QFP80)
      RF5C296      - Ricoh RF5C296 PCMCIA controller (TQFP144)
      M66220FP     - 256 x8bit Mail-Box (Inter-MPU data transfer)
      CAT702       - Protection chip labelled 'TT16' (DIP20)
      *            - These parts located under the PCB
      
      Note! FLASHROMs are not dumped, but can be _IF_ required.
            They shouldn't be needed though, as the devices are
            flashed (with data from the cart) by the hardware.

-