After creating an EPROM Emulator (see my other projects) I needed a simple Z80 platform for my experiments, only the basic minimum required components around the processor are provided, stuff that allows you to get the "blinky" program working (LED connected to IO port flashing).

The boards include:

• Z80 CPU
• 28 Pin socket for ROM (can be EPROM or EEPROM) - works well with my "EPROM emulator NG"
• 28 Pin socket for RAM (62256)
• IO Controller (82C55)
• Expansion bus (based on z50Bus)
• basic address decoder to run the ROM/RAM and I/O
• "experiments area" where you can add components
• option to run an oscillator module or discrete oscillator with quartz crystal.

The onboard address decoder logic provides the following:

• ROM at 0000h - 7FFFh
• RAM at 8000h - FFFFh
• IO at 00h (IOPortA)
• IO at 01h (IOPortB)
• IO at 02h (IOPortC)
• IO at 03h (Control)

The onboard address decoder can be disabled by jumpers and all CS signals for ROM, RAM, and IO are provided on the z50bus

http://linc.no/products/z50bus/

Join a "users group" on https://groups.io/g/mgh80/ to contribute further to the project, ask questions if you get stuck or to see what others do with the board.

Updates:

Oct-16-2021 Updated Gebers to 1.5 - added IO_WR signal to Z50Bus pin 41 to support the Serial Expansion Card.

Apr-23-2021 Updated Gerbers to 1.4 - Added LED to port PA0, can be disabled by a jumper.

Jan-02-2021 Updated Gerbers to 1.3 - made the holes in the "experiments area" larger to accommodate standard pin headers.

Dec-26-2020 Updated Gerbers to 1.2 - fix for the EEPROM compatibility with the onboard address decoder causing issues in v1.1