Basic NES Reproduction Board Guide

Please look at the main entry for more information!

Here’s a quick guide on how to populate my custom designed NES reproduction PCB. This is the “Basic” version that supports NROM, CNROM, AOROM, UNROM, and UOROM games.

Front Side

PRG EPROM

Needed for: All game types
Part Number: 27C256, 27C512, 27C010, 27C020, 27C040, 27C080
Function: Holds the Program ROM file

CHR EPROM

Needed for: NROM, CNROM
Part Number: 27C256, 27C512, 27C010, 27C020, 27C040, 27C080
Function: Holds the Character ROM file (sprite data)

CHR SRAM

Needed for: AOROM, UNROM, UOROM
Part Number: 6264 series
Function: Holds the ROM’s sprite data

CIC

Needed for: All game types (unless using a top-loader NES, modded NES, or clone console)
Part Number: Original CIC, or programmed ATTiny13
Function: Completes the region check and allows the game to run on the console

C1 – Electrolytic Capacitor

Needed for: All game types
Value: ~22 uF, at least 10 V rated
Function: Smooths out supply voltage for the board due to transients on the power supply, prevents quick changes in supply voltage when power is turned off. Please note to bend it over to the right, to avoid interference with the cartridge shell.

C2, C3, C4 – Ceramic Capacitors

Needed for: All game types
Value: ~0.1 uF, at least 10 V rated
Function: 
Filters out high-frequency noise that can interrupt the EPROMs, SRAM, and CIC

C5 – Ceramic Capacitor

Needed for: UNROM, UOROM
Value: ~0.1 uF, at least 10 V rated
Function: 
Filters out high-frequency noise that can interrupt the 74HC32

C6 – Ceramic Capacitor

Needed for: CNROM, AOROM, UNROM, UOROM
Value: ~0.1 uF, at least 10 V rated
Function: 
Filters out high-frequency noise that can interrupt the 74HC161

ROM/RAM Solder Pads

Solder the middle pads to either the left or right pads for either CHR ROM or CHR RAM. If you’re using NROM or CNROM, solder in the ROM direction. AOROM, UNROM, and UOROM require bridging pads in the RAM direction.

H/V Solder Pads

This is to set the mirroring mode for your game. Solder the middle pad to either H (horizontal) or V (vertical). This will vary from game to game. If you make a game, and the graphics are all screwed up, try soldering the other set of pads – this will often fix the problem.

Back Side

Solder Pads

Solder the pairs of pads together for your indicated board type. Make sure to solder all sets of pads, and make sure only one set is soldered at a time! Example of this can be seen below for an NROM game type:

For 27C256, 27C512, or other 28-pin EPROMs

There is a slight oversight on the board when using 28-pin EPROMs. You must solder pin 28 on the EPROM (or pin 30 on the socket) to pin 31 on the socket for the PRG ROM. A new revision of the board will fix this error. See the picture below for what this looks like.

One thought on “Basic NES Reproduction Board Guide

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s