Articles tagged “Konami Justifier”
The completed Light Phaser to Justifier adaptor
Since my previous post I've had a chance to test the Sega Light Phaser to Konami Justifier adaptor circuit with Lethal Enforcers II: Gun Fighters and it seems to work well throughout the game so I thought it was a good time to put the project into a neat box. The Mega Drive uses common DE-9 connectors for its controller ports. You can easily find metal connectors with lugs for panel mounting however I wanted to use plastic connectors similar to the ones on the original console – not just for a consistent look, but to also protect the plastic connectors on the Sega Light Phasers from being scratched by the sharp edges of metal connectors.
Electronics Konami Justifier Light guns Mega Drive light gun adaptor Sega Sega Light Phaser Sega Master System Sega Mega Drive
Adding some protective resistors to the Light Phaser to Mega Drive gun adaptors
Here's a quick update to the two Mega Drive light gun adaptor circuits, all to a few extra resistors in and around the adaptor and the console. The real Sega Menacer receiver drives the TH line (used to indicate when the gun has seen light) directly from the output of a NOR gate with a 470Ω resistor in series. My circuit uses a transistor in the open-collector configuration with a 10KΩ resistor on the base input and a 1KΩ pull-up resistor, which is the same as the circuit used in the original Sega Light Phaser.
Electronics Konami Justifier Light guns Mega Drive light gun adaptor Sega Sega Light Phaser Sega Master System Sega Mega Drive Sega Menacer
Simplifying the Light Phaser to Justifier adaptor to a two-chip solution
In the previous post I mentioned I was dissatisfied with the optimisation of the Light Phaser to Justifier adaptor circuit. This was because I was using two quad two-input multiplexer chips (eight multiplexers total) but only using three multiplexers on each chip but also needed two inverter gates and so had to add a third chip to accommodate that requirement. It seemed like there must be a better solution, and after pondering this in the shower I think I found it. One of the inverters is required for the transistor used to drive the TH line from the circuit.
Electronics Konami Justifier Light guns Mega Drive light gun adaptor Sega Sega Light Phaser Sega Master System Sega Mega Drive
Using Master System Light Phasers to play Konami Justifier games on the Mega Drive
Following my adventures with building an adaptor that lets me use Sega Light Phaser guns in Sega Menacer games it seemed sensible to turn my attention to the other type of light gun for the Sega Mega Drive – the Konami Justifier. The two Justifier guns in a photo from Wikipedia These guns are unsurprisingly incompatible with the Sega Menacer and Sega Light Phaser and supported in even fewer games on the stock Mega Drive (only Lethal Enforcers and Lethal Enforcers II: Gun Fighters). However, these games are more in line with the type of light gun game that I like to play than what you'd find in the Menacer's library (even though the digitised sprites haven't aged particularly gracefully) and the guns are eye-wateringly expensive if you want to get a set of both for two-player games which makes the idea of a cheap adaptor to use the Master System's Light Phaser more appealing.
Electronics Konami Justifier Light guns Mega Drive light gun adaptor Sega Sega Light Phaser Sega Master System Sega Mega Drive