View Full Version : Atari 2600 TIA - A 6526?

January 7th, 2007, 10:44 PM
I got a dead Atari 2600 Jr board out of the shed just now and compared it to the PAL schematics on the net. They say the TIA (Television Interface Adapter) is a custom chip. My Atari has a boring old 6526 CIA on it, like the ones used in C64's.

I think...

Is it just a coincidence the part number is the same or is it really a 6526? Being able to generate colour video signals with a 6526 would be fun.


January 25th, 2007, 12:46 PM
The 2600 is made up of 3 chips:

6507 CPU
RIOT (generally a 6521 or like)

So the 6526 is a variant of the VIA (Versital Interface Adapter) used is ever Atari 8bit computer, 2600, 5200 and 7800 game systems by Atari as well as the C64's


January 26th, 2007, 04:37 AM
Yes, VIA = 6522, CIA = 6526 (later semi-compatible with 8520 IIRC). The 6522 is found in many early Commodore products (PET, VIC, floppy drives etc). If someone had installed a CIA in place of a TIA, no wonder if the video game doesn't work. :-P