Above is a picture of my 2600 Monocart. It's a "Flash cart" for the Atari 2600, featuring an ATtiny461 with a AVRUSB-based firmware. It also features a EPM3064 CPLD that will perform the various bankswitching stuff you can find on many 2600 carts.

I've called this project "Monocart" (as opposed to "Multicart"), because the memory size is only 32Kb, so don't expect to load tons of games into it ;)

I wanted to make the board as convenient as possible : all DIP and PLCC components (with the exception of a 3.3V LDO regulator), and standard programming headers available on the board itself.
I managed to have it work properly, but not as I intended at first. I planned to use a NVRAM chip, so it would have been able to emulate the additional RAM you can find on some carts. However, for some reason, the chip doesn't work as expected. I ended up using a standard EEPROM (28C64) and it went fine. So let's call it half-successful ;)

Now I need to write some kind of "bootloader", that will set up bankswitching, and maybe display a nice logo too ;) and write all the bankswitching logic you can find on 2600 carts (there are many of them, due to the limited 4KB address space of the 6507 CPU used in the 2600).

Later, I will try to figure out why it doesn't work with the NVRAM chip. I tried to use it on a Pixel Past PCB (suspecting a flaw in my own board design) and it failed too.