7800 Console Testing

I have been going through and testing all of my 7800 units off and on for a month or so. I wanted to see if any of them were truely 100% compatable with all 2600 and 7800 titles. Unfortunately I did not have any of the most recent models such as the "A3" or "X" units to test.

I also took this opportunity to compare serial numbers with motherboard build dates.

Below is a summary table I put together.

Conclusions:
In regards to compatability there is nothing consistent. I did end up with 3 units that could play anything I threw at them, but having a similar unit to these is no guarantee of 100% compatability.

I used the 7800 Diagnostic cart to calibrate the color and to check for errors.
I used Double Dragon to test the consoles 2-button functionality for each player.
Food Fight, Dark Chambers, and Santa Simon were checked to see if they would load and play fine.

All units worked fine with Food Fight and Dark Chambers. Santa Simon did not work on 2 units and was almost playable on another.

For 2600 testing I used both cartridges "(C )" and the Harmony cart "(H)". It was interesting that using the Harmony cart gave me near 100% compatabiltiy for all units. Another great reason to get one! For the two instances where Burgertime did not work via Harmony the real cart worked fine. :ponder:

None of the units had problems with the real cart versions of Burgertime, Kool-Aid Man, or Stargate.
Time Pilot was easily the most difficult cart for the 7800 units to handle, followed by Decathlon.

The Color Bar Generator and TestCart were not for compatability but I did use them for console functionality and color calibration (2600 mode).

For the early units (EP, AT84&85), the motherboards and serial numbers did not follow any sequence. An early serila number is not a guarantee that the motherboard is an early model as well. Even my "test market" EP motherboard was made in the 24th week of 1984 whereas another unit had a motherboard made in the 21st week. I guess Atari made a bunch of motherboards in 1984 and when they were assembled into the casings then it was whatever the person on the assembly line grabbed.

Also, I did have three units with the different rainbow pattern on the front of the 7800, including my "early" EP unit. These are marked with an (*). Normally, most rainbows on the 7800 start in yellow and end in green, but few start in red and end in purple. This is cool as it corresponds to the actual visual spectrum of light (a real rainbow).

Also, my lowest serial number AT84 unit only has a hole for the expansion port but no pins. It is also made in teh 27th week of 1984. This is wierd as other models made in 1986 or 11987 still had the full port with pins. Maybe this was simply an error?

Anyway lots to look at here and if I ever get more units then I will keep this updated.