This is a modified Ben Eater 6502 Computer PCB board that I’ve been working on. It has a serial I/O port so that I can send and receive data to a display like my laptop, LCD, or CRT monitor. I used Grant Searle’s video and keyboard interface circuit and found a blog that helped with setting up the serial I/O using a 6551 ACIA chip. So far, all it is doing is running a version of Wozmon that I found on reddit, but I eventually want to port a BASIC interpreter just like the apple 1. See the links below for the sources I used.
Ben Eater 6502 videos: https://youtube.com/playlist?list=PLowKtXNTBypFbtuVMUVXNR0z1mu7dp7eH
Blog I used for adding serial to BE6502: https://mike42.me/blog/2021-07-adding-a-serial-port-to-my-6502-computer
Video and Keyboard interface: http://searle.x10host.com/MonitorKeyboard/index.html
Version of Wozmon I found on reddit: https://www.reddit.com/r/beneater/comments/k14gko/comment/gdm391d/?utm_source=share&utm_medium=web2x&context=3
https://github.com/kissmywhat/sd/blob/master/woz_sd.asm
Some resources for learning about NTSC and Composite video: https://www.youtube.com/watch?v=X24zDXz8Xgc
http://www.kolumbus.fi/pami1/video/pal_ntsc.html
https://sagargv.blogspot.com/2011/04/ntsc-demystified-part-1-b-video-and.html
Here is a link to my github with the KiCAD schematics and AVR makefile: https://github.com/The-Invent0r/6502-Computer-PCB