Sega Naomi Gd Rom Service Manual

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2 - 3  MONITOR DIRECTION AND HORIZONTAL SCANNING FREQUENCY
• MONITOR DIRECTION
Install the monitor in the positional direction (horizontal or vertical as applicable) suitable
for each game.  For the monitor direction, refer to the attached manual of the specific game.
If the attached Instruction Manual dose not refer to the monitor direction, postion the
monitor in the horizontal direction.
HORIZONTAL
• HORIZONTAL SCANNING FREQUENCY : 15.85kHz / 31.69kHz
Which one of 15kHz or 31kHz frequency, or both...

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BCA
B
2 - 4  REPAIR/SERVICING AND CARTON BOX
When  transporting  the  NAOMI  board  (or  NAOMI  2  board)  and  the  GD-ROM  drive  for  repair/
servicing,  follow  the  instructions  below.  The  carton  box  (a  standard  accessory)  is  needed  when
transporting these components for repair/servicing. Carefully keep, therefore, the carton box.
• For repair/servicing, ship a set of the following parts:
NAOMI board case
DIMM board case
* Do not remove the key chip but leave it attached.
GD-ROM drive
*...

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FIG. 2. 4 b
CARTON BOX
601-11031
FIG. 2. 4 c
CARTON BOX
601-11030
Remove the GD drive bracket. 

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3.  ASSEMBLING THE NAOMI GD-ROM SYSTEM
Before starting to work, ensure that the Power SW is OFF.  Failure to observe this
can cause electric shock and short circuit hazards.
Assemble the NAOMI GD-ROM system as follows:
When the GD-ROM system is used with:
a standard cabinet that contains the NAOMI board:
a JVS-compatible standard cabinet:
The purchased NAOMI board case has come with the DIMM board?
Referring to the Section 3-1, "CHECKING THE BOOT ROM VERSION
NUMBER," check the version number....

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When the GD-ROM system is used with a dedicated game cabinet:
Referring to the "Owner's Manual" attached with each game machine,
install the GD-ROM drive and connect the wires.
Referring to the Section 3-4, "KEY CHIP," attach the key chip.
Referring to the Section 3-5, "GD-ROM DISK," attach the GD-ROM
disk.
Referring to the Section 3-6, "CONNECTING THE POWER," connect
the power.
3 

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3 - 1  CHECKING THE BOOT ROM VERSION NUMBER
You can use the NAOMI main board for a GD-ROM system only if its boot ROM version
number is EPR-xxxxE or later. The five-digit version number is indicated on the sticker of the
boot ROM (IC27) of the NAOMI main board.
Visually check the boot ROM sticker and make sure that the version number is as follows:
EXAMPLE : EPR-XXXXXD X (Not usable for a GD-ROM system)
EPR-XXXXXE O (Usable for a GD-ROM system)
EPR-XXXXXF O (Usable for a GD-ROM system)
FIG. 3. 1
When...

10
3 - 2  BOOT ROM REPLACEMENT
Do  not  perform  this  work  unless  otherwise  particularly  instructed  due  to  BOOT  ROM  version
change, etc.
Remove on-socket ROM (IC27) of NAOMI Main BD from the socket by using an IC EXTRACTOR.
• To prevent tearing off on-board patterns, etc., do not used tools such as a flat-blade type screw-
driver,  etc.  other  than  the  IC  EXTRACTOR.    For  malfunctioning  resulting  from  using  tools
other than the IC EXTRACTOR, repair shall be performed on a pay-basis....

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Insert a new ROM into a socket; be careful about an inserting direction in this instance.
• It may be uneasy to insert a ROM, because the width between the two lines of pins on both
ends may be larger than required. If this is the case, press the ROM pins onto a flat surface
and bend them; thus make the width smaller.
• When inserting the ROM, be very careful to insert it into a correct direction and not to break
its pins.
Inserting positions are shifted.
Inserting positions are shifted.
Inserted...

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3 - 3  DETACHING/ATTACHING THE DIMM BOARD CASE
How to Attach
Contact the connectors with each other, and insert the DIMM board case into the NAOMI board
case; be careful about an inserting direction in this instance. Make sure that the DIMM board
case is seated firmly and completely.
Use the three M3 X 30 screws and one M3 X 70 screw that fix the DIMM board case onto the
NAOMI board case.
How to Detach
Remove the three M3 X 30 screws and one M3 X 70 screw that fix the DIMM board case onto
the NAOMI...

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3 - 4  KEY CHIP

The key chip is a precision device. Handle it carefully because it may be
damaged by heat, shock, and static electricity.

The key chip is contained in the GD-ROM disk case. Always use them as a
set.
How to Attach
Remove the key chip from the GD-ROM disk case.
Insert the key chip vertically into the slot of the DIMM board case; be careful about an inserting
direction in this instance. Make sure that the key chip is seated firmly and completely.
How to Detach
Pressing the tab of the...