Firmware, RomWBW

To summarise RomWBW, I’ll quote Wayne Warthen, author of RomWBW:

RomWBW is a ROM-based implementation of CP/M-80 2.2 and Z-System for all RetroBrew Computers Z80/Z180 hardware platforms including SBC 1/2, Zeta 1/2, N8, Mark IV, RC2014, and Easy Z80. Virtually all RetroBrew hardware is supported including floppy, hard disk (IDE, CF Card, SD Card), Video, and keyboard. VT-100 terminal emulation is built-in.

The RomWBW ROM loads and runs the built-in operating systems directly from the ROM and includes a selection of standard/useful applications accessed via a ROM disk drive. A RAM disk drive is also provided to allow temporary file storage.


RomWBW is freely available on github , together with source code and documentation.

To get the very latest version of these documents, and others not linked above, download RomWBW from github and unzip it. The documentation files can be found in the “Doc” folder.

You can upgrade your RomWBW installation by following these instructions.

If your hardware supports RomWBW and you want to run CP/M, I recommend you use RomWBW. The hardware requirements are primarily:

  • A Z80/Z180 Family CPU
  • 512k bytes ROM
  • 512k bytes RAM

Optional hardware:

  • Asynchronous serial port(s)
  • Compact Flash for mass storage
  • SD card for mass storage
  • IDE hard drive for mass storage
  • Real time clock
  • Keyboard
  • Video display unit

Pocket-sized Z180 RomWBW CP/M computer

SC131 is a Z180 based pocket-sized computer designed to run RomWBW.

System based on SC130 (Z180 motherboard)

SC130 is a Z180 motherboard which can run RomWBW without any additional expansion modules.

System based on SC126 (Z180 motherboard)

SC126 is a Z180 motherboard which can run RomWBW without any additional expansion modules.

System based on SC111 (Z180 module)

SC111 is a Z180 module for an extended RC2014 bus. It is designed to be used with memory module SC119.

System based on SC503 (Z180 card)

SC503 is a Z180 card for the Z50Bus.

Systems based on the RC2014 bus

The requirements to run RomWBW on the RC2014 bus or extended versions of the RC2014 bus, are:

Homebrew 8-bit retro computing