Sega Mega Drive In-Game-Reset Install Guide

This guide will show you how to install the in-game-reset mod from Borti4938 into a Sega Mega Drive.

In-Game-Reset Pinout

Installing this In-Game-Reset chip is very straight forward. No trace cuts are required. Just stick down the chip and make the connections and it should be working. Avoid running wire over the cartridge port area,

This In-Game-Reset chip will work with any switchless modded Mega Drive, however it is best paired with the switchless region mod by Borti4938 which is used with the switchless region mod kits sold here.

Board Maps

Pin 1 – Power

Connect this to a +5V pad on the region jumpers.

Pin 2 – Mode Set

Connect Pin 2 to either +5V or leave it with No Connection (N.C)

When No Connection (Not Active)

  • Holding the controller buttons Start+A+B+C for 1.5 seconds will reset the console.

When +5V Connection (Active)

  • Holding the controller buttons Start+A+B+C for 1.5 seconds will reset the console.
  • Keep holding and the console will cycle through the console regions if there is a switchless region mod installed.
  • During this reset-hold the game will be paused if Pin 6 is connected to the CPU HALT pin.

You can bridge Pins 1 and 2 together with solder at the chip to activate this mode.

Pin 3 and Pin 4 – Controller Port 1

Need soldering to Controller Port 1

  • Pin 3 to Controller Port Pin 6 which detects when A+B is pressed.
  • Pin 4 to Controller Port Pin 9 which detects when C+Start is pressed.

Pin 6 – CPU Halt

Connected to:

  • MD1 CPU Pin 17

When this is connected the game will pause when START+A+B+C is held long enough to start cycling through the console’s regions. Only connect this if you want the game to pause when
cycling through the regions. CPU Halt only works when MODE SET is Active / connected to +5V.

Pin 7 – Reset Button (In)

This pin has to be connected to the reset button. This can be connected to the Reset Button pin on the board or if you have a switchless region mod installed, ‘PIN 13 – RESET BUTTON (IN)’ of the switchless region mod chip. Connecting to either is functionally the same.

The same applies to all other matching pins of a switchless region mod chip and the IGR mod chip. Power, Ground, Reset Button.

Pin 8 – Ground

Connect this to a Ground pad on the region jumpers.