7800 Expansion port? What tha hey?

[Raedon]

I have 2 7800's here and one has an expansion port on the left side, the other does not but has the hole in the RF for it. I take it they were planning something and it never happened so they dumped it on future consoles?

[zektor]

I remember when I first purchased the 7800 seeing the expansion and thinking "Wow! I wonder what cool peripheral will go here!". GUess I'm still left to wonder...

[Raedon]

No way!! Check this out! Looks like S-Video is a lot easier then what they are doing over at atariage! lol

Check out all the stuff you can hack threw that port!

http://invalid.ed.ntnu.no/~kamben/hw...Atari7800.html

[zektor]

That is cool. You can most definitely hack video/audio outputs through that expansion if the data in the schematic is correct...

[Raedon]

Hmm. . after finding out more info I think that the port has video and audio inputs not outputs.. I'm guessing that a 5200 Expansion module would have gone here. Still looking, not much info about this out there.

from the 7800 faq at Atariage

model revisions:

Atari CX7800 - Vastly modified and enhanced 2600 model. Two joystick ports on lower front panel. New chipset (except sound chip; pokey chips could be added to carts). Side expansion port for upgrades and computer add ons. Bundled accessories included two CX24 ProLine joysticks AC Adapter, switchbox, RCA connecting cable, and Pole Position II cartridge.

Atari CX7800 - Second Revision. Slightly revised mother board, added an addional timing circuit. Expansion port connector removed from mother board but is still etched. Shell has indentation of where expansion port was to be.

Atari CX7800 - Third Revision. As above but only a small "blemish" mark on shell.

Also this info..

What 7800 hardware was announced, but never released?
7800 Keyboard, peripherals and computer games designed by GCC. There was also a 7800 adapter for the 5200.

Audio info:

Expansion Port Audio
There is no audio signal output on the expansion connector pin 17. Introducing an analog audio signal on this pin produces no results, whether this is because there needs to be a flag set in one of the I/O chips to enable external audio mixing (which I suspect is the case) or whether it is expecting a digital signal, I don't know.

In any case, you can't pick up an audio signal from here for a separate audio output.