The module has the following features:

• 1 MB accessible 8-bit memory
• 512 kB RAM
• Two firmware options via two 512 kB Flash ROMs
• Required ROM selected with a toggle switch
• The kit includes RomWBW and SCM firmware
• Jumpers to swap RAM/ROM positions in memory map
• Compatible with Z80 style ROM at bottom of memory
• Compatible with 68xx style ROM at top of memory

An RCBus 80-pin backplane is required, such as SC700 series backplanes.

This module is a simple linear 1 MB memory module without a memory management unit (MMU). Therefore, the processor module must provide all 20 address lines to the bus. Suitable processor modules are SC722 (Z180 CPU) and SC730 (Z80 CPU). It is not compatible with processor modules that do not include a MMU, such as SC706.

There is a choice of firmware for this module: When used with a Z180 CPU (eg. SC722) the firmware is RomWBW SCZ180_SC700 and SCM S9. When used with a Z80 CPU (eg. SC730) the firmware is RomWBW RCZ80_std and SCM S7.

Documentation

The documentation can be found at www.smallcomputercentral.com

Compatibility

This module conforms to the RCBus specification v1.0 for RCBus-Z80 and RCBus-68xx.

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

The full kit includes all the components needed to make the module, as shown in the first picture. Other modules and backplanes shown in the other pictures are not included. You will require tools, solder and cleaning materials to assemble this kit.

Printed Circuit Board

The printed circuit board is available on its own here.

Complete Systems

If you are looking for a complete system the following products might be appropriate.

• SC126 RCBus-80pin Z180 RomWBW CP/M Motherboard
• SC720 RCBus-80pin Z80 RomWBW CP/M Motherboard
• SC791 RCBus-80pin Z80 RomWBW CP/M Computer
• SC792 RCBus-80pin Z180 RomWBW CP/M Computer
• SC114 RCBus-40pin Z80 SCM & BASIC Motherboard
• SC131 Pocket-sized Z180 RomWBW CP/M computer

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.