SC202 – Boards for a flexible Z80 computer

This set of six printed circuit boards is designed to build a flexible Z80 system.

The system can be expanded to run CP/M and more.

Set of boards consisting of:

SC202 PCB Image Green Top
SC202 – Set of boards to build a flexible Z80 computer

Once built this minimal system contains:

  • Z80 processor
  • 128k bytes RAM
  • 32k bytes EPROM
  • 7.3728 MHz clock
  • Z80 SIO/2 dual port serial interface
  • Z80 CTC 4 channel counter timer
  • Z80 PIO parallel I/O interface
  • Backplane with power input and 2 spare slots
  • Backplane extension with 6 spare slots
PCB complete
SC102 – Z80 CTC 4 channel counter timer (shown here in blue)
Complete 1
SC103 – Z80 PIO parallel interface module (shown here in blue)
SC104 Assembled
SC104 – Z80 SIO/2 dual port serial interface (shown here in blue)
Build 2 without sockets - cropped
SC108 – Z80 CPU, RAM and ROM module
SC112 v1.0 Assembled - 2
SC112 – 6-slot backplane with power input
SC113 v1.1 Assembled - 1
SC113 – 6-slot backplane extension

Each board has a user guide which includes component sourcing and assembly details. These documents can be found on the documentation page of this site.

Communication to the outside world is achieved using the included serial board connected to a terminal or with an FTDI style serial adapter cable connected to a computer running a terminal emulation program.

This Z80 computer is designed to run the free Small Computer Monitor software version 1.0 configuration R3. Program a 32k byte EPROM (27C256) with this code and you have a capable machine code monitor, a BASIC interpreter and a CP/M loader.

To upgrade to a CP/M system, just add an RC2014 Compact Flash module and Compact Flash card containing CP/M.

Set 02 in use - cropped

You can purchase this set of printed circuit boards from Tindie.


  • This design is made in accordance with the “designed for RC2014″labelling scheme.
  • RC2014 is a trademark of RFC2795 Ltd.
  • This product is designed for hobby use and is not suitable for industrial, commercial or safety-critical applications.

Homebrew 8-bit retro computing