In 1979, Mattel tried their hand at videogames. They wanted to take on
the 2600 in the video game market. Their offering was the Intellivision.
The InTV's claim to fame was it's selection of "life-like" sports games
and it's two-player-only games. The slight problem was the 2600 had the
backing of atari and hence it get all the cool arcade translations! Still,
the InTV had many great original titles to choose from.
First true 16 bit home console. The processor is a CP1610 (CP1600 with a low clock rate (read: cheaper!)) running at 894.886 Khz. This processor is very weird. It's got a multiplexed address and data bus (similar to the 8051/8085). All 16 bits bits are multiplexed however. This bus handles the 16 data lines and the 16 address lines. There are three bus control signals that determine what the data on the address/data bus means. These three lines describe one of eight actions to perform (2 to the 3rd is 8). Typical states are address latch enable, read enable, write enable, and interrupt acknowledge. Note that there is no external address decoding like in any other microprocessor system in existance. The chips on the bus must do all address decoding themselves!! Yes, this includes the carts too! If you open up a cart with multiple ROMs, you can see that they are all bussed together (since the ROMs themselves do all the address decoding :-). The rest of the system consists of the STIC or Standard Television Interface Chip (which has it's own RAM (graphics RAM (GRAM)) and it's own ROM (graphics ROM (GROM)). There's also another special RAM chip that acts both as general purpose RAM for the processor, and as a sort of video buffer for the STIC (tells what characters to show where on the screen). A BIOS ROM called the Exec rounds out the system. Said ROM holds often-used things like score routines, generic sound effects, math routines, etc.