SC602 is a memory module with two 512KB FLASH ROMs and one 512KB RAM, designed for the 40-pin RC2014/RCBus. This module provides suitable memory for running RomWBW, CP/M and the Small Computer Monitor (SCM).

Only one of the FLASH ROMs is enabled at a time. This is selected with a switch. Typically, one ROM contains RomWBW and the other contains SCM.

The top 32KB of the 512KB RAM is always mapped to the top 32KB of the Z80's memory space (0x8000 to 0xFFFF).

At reset the bottom 32KB of the 512KB FLASH ROM is mapped to the bottom 32KB of the Z80's memory space (0x0000 to 0x7FFF).

Any of the sixteen 32KB FLASH ROM banks (0 to 15) or any of the sixteen 32KB RAM banks (16 to 31) can be mapped to the bottom 32KB of the Z80's memory space (0x0000 to 0x7FFF) with a single write to I/O address 0x78 (or 0x79).

Documentation

The documentation can be found at www.smallcomputercentral.com

Compatibility

This module conforms fully to the RCBus specification v1.0 for 40-pin systems.

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.

All of the integrated circuits supplied in this kit are brand new parts from major suppliers, such as Mouser, DigiKey, RS and Farnell.

The kit includes two FLASH ROMs. One contains RomWBW and the other contains SCM.

Printed Circuit Board

The printed circuit board is available on its 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.
• RC2014 is a trademark of RFC2795 Ltd.