AV Pinout (Neo Geo AES)
The Neo Geo AES has the exact same pinout as the Master System 1 and Mega Drive / Genesis 1, but the top left and right pins are closer in than the Master System / Mega Drive.
This means that a composite cable with only the bottom 5 pins will fit in the Master System / Mega Drive 1 and Neo Geo AES and all be the same identical cable. However RGB cables will be different for the Master System / Mega Drive than the Neo Geo AES due to the top pin positions.
Here is the pinout looking into the console.
The Neo Geo AES already has RGB video output and can be internally modified for better RGB. Here is the pinout of the RGB cable.
The Neo Geo AES natively supports RGBs (CSYNC) output on the AV port.
Each version of the Neo Geo has slightly different voltage specifications.
Based on the actual RGBs specifications, the Red Green and Blue lines should be 0.7V once terminated (connected to receiver).
The csync voltage should be 0.3V when terminated.
What we find on the early revision Neo Geo NEO-O that I have for example, the Red, Green and Blue lines are 1.1V unterminated and 550mV terminated, meaning it is slightly dull and needs bringing up 0.3V.
The CSYNC line is 1.1V unterminated and 400mV terminated, so also slightly over voltage.
This tolerance is acceptable for the OSSC converter and many PVM and CRT monitors, however for perfect specification it should be corrected.