Odyssey 2 ROM Pins Topic:Odyessey 2   Date: 2004-04-23 Printer Friendly:

Here is a graphic showing the O2 ROM cartridge slot pins:

Here is the fig file. For more information on using the fig file, see xfig.org. I used the pin names for the 8048 pins, rather than names specific to the Odyssey, since most of the pins go directly to the 8048. The only exception is pin 5 on the back row (as you look at the console from the front). You set P16 high, and that allows RD to affect the output of the NAND gate (which is connected to pin 5). If P16 is high, then one of the inputs on the NAND gate is high. The other input to the NAND gate is high when writing (well, not reading). I don't entirely understand it, but that is what I have so far.