6502.org

Hey,

I've decided I want to build my own 6502-based computer. I've been reading a lot lately and even coded a 6502 emulator in Go (not published yet).

I'm now looking at how to design this computer. Obviously I need a 65C02, and some other things. I've just figured out address decoding using a 74HC138 (read more about that at http://i6502.tumblr.com/post/9224126019 ... s-decoding ).

My questions now are:

* How do I continue from here? What is a good distribution of RAM, I/O and EEPROM?
* Given I want 32kB RAM, 16kB ROM and the rest reserved and for I/O, do I still need the 74HC138, or are there better solutions?
* I have found a 32kB SRAM module, is this a good one to use for this project? https://www.jameco.com/webapp/wcs/store ... ctId=82472
* I have no clue about how to make I/O work, all I know is that I probably need something like a W65C22S6TPG-14.
* What is a good EEPROM unit? I have no idea about EEPROM and how to re-program that stuff.

Sorry for all the newbie questions, hope someone is willing to help me in the right direction.

Edit: Fixed the 75HCxxx typo issue.

See the 6502 primer, starting at http://wilsonminesco.com/6502primer/index.html. It will answer most of your questions and a lot more that will come up as you progress.

As for the SRAM, yes, the 62256 is a good choice. For ROM, you'll probably want the 27c128 (16Kx8 EPROM) or 27c256 (32Kx8 EPROM) or the same things starting with 28 instead of 27 for EEPROM. There's a topic on (E)EPROM programmers at viewtopic.php?f=4&t=2974.

Don't apologize for too many questions. Except for those who don't do any of their own research (and apparently you already have done some yourself), we like for people to ask all the questions they need to to be successful.

You mean a 74HC138?

Yes, very much! I ran into that looking for parts as well. Not sure why I have that issue typing that part number.