Two old good Z80 projects and two vintage 6502 projects by Hackman's Realm. Enjoy the past time...

The first great Z80 project: This is the culmination of various sub-projects involving the study of the Z80, an EEPROM chip, and the 6522 VIA I/O chip. This project is actually a fully functional mini-computer which you can build on a single breadboard. It won't really do very much, but if you want to study computer engineering and you've never actually built something like this before, this is probably a decent place to start.

Parts used in this project:
Z80 CPU chip
2865 EEPROM chip
6522 VIA (Versatile Interface Adapter) I/O chip
4093 Schmitt trigger NAND gate chip
7404 NOT gate chip (Also known as an inverter)

The second great Z80 project: After having success making a single-board, Z80-based computer that can turn on a LED, you may wish to make a computer with slightly enhanced output capabilities. To this end, this second project will connect an industry-standard graphical LCD screen to the Z80, and allow you to draw things on it. Although this project is still pretty simple and doesn't draw anything more than three bars on the display, the beauty of it is that you can draw anything you want, simply by re-programming the ROM chip. Just as with more complicated and modern computers, the hardware is just a framework, from which you can do just about anything imaginable through software.

These projects reworked for a 6502 microprocessor:

The first great 6502 project: This project pretty much duplicates the function of the First Great Z80 Project. It uses a 6502 with a ROM chip and a 6522 VIA to control some LEDs.

Chips used:
6502 CPU chip
2865 EEPROM chip
6522 VIA (Versatile Interface Adapter) I/O chip
74LS138 3-to-8 decoder chip
7404 NOT gate chip (For the CPU's clock circuit)

The second great 6502 project: After making a 6502-based single-board computer to make a cute little pattern of alternately on and off LEDs, you may be up for something a little more visually capable. To that end, this project straps an industry-standard graphical LCD to a 6502 system and allows you to display things on it. Although this project is still pretty simple and doesn't draw anything more than three bars on the display, the beauty of it is that you can draw anything you want, simply by re-programming the ROM chip. Just as with more complicated and modern computers, the hardware is just a framework, from which you can do just about anything imaginable through software.

Enjoy