In the early decline of Atari 2600, Intelivision came along. It was suppose to be superior to the 2600, but the games that came out for Intelivision were also ported to the 2600.
The only difference I can remember was the user interface. The Intelivision had a control pad had many more buttons and a joystick like rocker panel. So Intelivision came out with games to use those controls.
When they were ported over to the 2600, the graphics and sounds were almost the same but the interface was ‘dumbed down’ to be playable on the 2600 joystick and single button.
The ported game cartridges were actual Intelivision molds with a 2600 adapter slapped on the end - does this mean that the chips inside could actually be used in either unit?
So how much more advanced was Intelivision over the 2600?