A modular RCBus Z80 based computer designed to run RomWBW and CP/M

SC791 RCBus-80pin Z80 RomWBW CP/M computer kit

Sold by Small Computer Central

$1.00

No tax for United States [change]
for unpowered backplanes SC702 and SC710
Stock available: 5
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The base computer, as selected with the default options on this page, includes all the parts shown in the first picture. It has a Z80 processor, 512k bytes of RAM, 512k bytes of Flash ROM, two 115200 baud serial ports, a regulated power supply (from an 8 to 15 volt input), and a Compact Flash interface. You will need to provide your own Compact Flash card. You will also require a power source that provides between 8 and 15 volts D.C. at up to 1 amp.

The kit is supplied with RomWBW pre-programmed into the Flash ROM. RomWBW includes CP/M and a range of useful software. It also supports a wide range of add on hardware. RomWBW has been provided free of charge by its author Wayne Warthen. Thank you, Wayne, for providing this and all the support.

The base computer is formed from the following backplane and modules:

  • SC710 - Backplane, 12 vertical sockets, 1 horizontal socket
  • SC703 - Power supply (8 to 12 volt input) and reset module
  • SC706 - Z80 central processor module
  • SC714 - Z80 memory module, 512k bytes RAM, 512k bytes Flash ROM
  • SC716 - Z80 dual serial input/output module
  • SC715 - Compact Flash module

The backplane, SC710, has 12 vertical module sockets and 1 horizontal socket. Alternative backplanes are available with a different number of module sockets. Some of the backplanes do not include the power and reset functions but instead provide header pins allowing them to extend other backplanes. These backplanes, SC702 and SC710, require a dedicated power and reset module, such as SC703 or SC712. Other backplanes, such as SC701 and SC709, include a 5 volt power input, and a voltage supervisor and reset device. These do not require a power supply module.

Recommended accessories:

  • SC302 - Serial to USB adapter
  • SC305 - Adapter cable, 6-way
  • SC306 - USB cable A to mini-B
  • SC719 - Digital I/O module
  • SC727 - Real time clock module

A number of options are provided to customise the kit. These include optional accessories and modules, and alternative parts, such as backplanes and power supply modules.

Documentation

The documentation can be found at www.smallcomputercentral.com

Compatibility

This module conforms to the RCBus specification v1.0 for RCBus-2014 and RCBus-Z80.

The RCBus specification includes RCBus-2014 (both RC2014 standard 40-pin bus and RC2014 enhanced 60-pin bus) and also the full 80-pin RCBus. The 80-pin RCBus provides support for advanced Z80 features, such as the interrupt daisy-chain, as well as support for other processor families.

The Kit

This kit includes all the components needed to make the computer, as shown in the first picture, except for the Compact Flash card. Other modules and backplanes shown in the pictures are not included. You will require tools, solder, and cleaning materials to assemble this kit.

You will need to provide your own Compact Flash card. Cards between 64MB and 2GB are generally recommended.

A power source to match the options selected is also required. The power source will need to be either 4.75 to 5.25 volts at up to 1 amp, or 8 to 15 volts at up to 1 amp.

Printed Circuit Board

The printed circuit boards are available on their own here.

Notes

  • This product is supplied as a kit of parts that require assembly.
  • It is your responsibility to pay any import duty or taxes charged by your home country.
  • This product is designed for hobby use and is not suitable for industrial, commercial or safety-critical applications.
  • RomWBW is copyright Wayne Warthen and has been provided free of charge with his permission.
  • The Compact Flash interface circuit has been designed by Tadeusz Pycio and reproduced with his permission.

Links to code and documentation

Documentation (smallcomputercentral.com)

Product HS Code: 854290

Shipping policy

Products usually ship within 3 days

The seller

Small Computer Central

Stowmarket, England, UK
3 orders since Feb 14, 2023
Retro computer kits