13 07 2017
I’ve recently been interested in my old Playstation 2.
Having played with the Playstation 2 when I was younger I remember the fun my brother and I had playing Time Crisis 3 with the G-CON 2 and the G-CON 45.
Now, most (all?) older version light guns don’t work on the newer flat screen TVs.
This is because of how they process / display the frames.
I researched how the G-CON45 works and it uses what’s known as the cathode ray timing method.
To my understanding, every H-SYNC increases the Y-coordinate by 1. The X position is determined by the timing between two H-SYNC and when the sensor sees the change in brightness of the “pixel” on a CRT TV, due to the electron beam hitting the phosphor.
Then it’s just a matter of passing on those coordinates to the Playstation and a bit of collision detection to determine if you hit a “bad guy” or not.
After a bit of research on google, I couldn’t find any claims that approved or disapproved my understanding of the G-CON 45.
So I did what I usually do, crack it open, see what’s inside and google again.
Here’s the PCB reverse engineered. It’s a small board and didn’t take too long to make.
The capacitor values might be wrong, I’m using one of those €20 component tester.