In a bygone age, the video game industry largely consisted of “dedicated” machines, that could play the games they were made to play and nothing else. Customers would buy devices costing $100 or more in 1970s dollars that could only play Pong and maybe a handful of other games, and that was it. It was a weird time.
There was a whole cottage industry of special chips devised by fabricators back then, that a manufacturer could buy from them, build a plastic shell around with AV connections, a few switches, and controllers (often hard-wired to the machine), and just like that have a console read to sell. The company General Instruments in particular sold a lot of these chips. Many of the details of this era can be read on the website Pong Story.
In addition to GI, Texas Instruments, National Semiconductor, and even MOS Technologies, makers of the 6502, got in on the dedicated video game chip business. MOS’s angle was to make customized chips that had a bit of built-in ROM that could run small programs without having to have a separate chip to store game code.
This was a fairly brief in the history of video gaming, and only a few consoles were made using these chips, all of them very obscure today. The always great blog Old Vintage Computing Research recently hunted down some of these consoles and tried them out. It’s a big article, and it makes for fascinating reading, to those of a certain mind. Of those, I am one. I suspect that you might be one too!