This card is designed for firmware developers.

It provides the read-only memory for a Z80-based system. In this case, however, the term “read-only” is not really correct as data can be written to it.

The card houses a FLASH chip which contains the boot-up firmware, such as the Small Computer Monitor (SCM). It also houses a “shadow” RAM chip (pseudo-ROM) which is arranged such that writing to the ‘ROM’ area causes the data to be written to the “shadow” RAM.

Once the “shadow” RAM contains the required firmware image, the memory select switch can be used to reconfigure the memory such that reading is from “shadow” RAM, which is now write-protected.

The main features are:

• 128k bytes FLASH (4 banks of 32k bytes)
• 128k bytes RAM (shadow ‘ROM’)
• Status LED
• Jumper selection of memory bank, or
• Software control of memory bank
• Write protect jumper for FLASH memory
• Compatible with Z80 CPU card SC518 plus memory card SC519
• Compatible with Z80 processor SC516
• The card can be disabled by writing to port 0x38

A typical system will also requires:

• Backplane (eg. SC501, SC508, SC515, or SC522)
• Power and reset card (eg. SC502)
• Z80 CPU and memory:
• • Z80 processor card (eg. SC516 with ROM chip removed), or
• • Z80 CPU + Z80 memory (eg. SC518+SC519 with FLASH chip removed)
• Serial card (eg. SC511, SC520, or SC521)

The Kit

The kit contains everything you need to build the card, except solder, tools, and cleaning materials. To use the completed card you require a backplane (eg. SC501), a power/reset card (eg. SC502), a Z80 CPU and memory card (eg. SC516), a serial card (eg. SC511), a USB to serial adapter (5-volt power and 5-volt signals), a computer, and a terminal program, such as Tera Term.

The supplied FLASH chip is programmed with the Small Computer Monitor (SCM) configuration F2.

To run CP/M you will need a mass storage card, such as SC504 (Compact Flash card interface).

Documentation

This product has a user guide and an assembly guide. The documentation can be found at www.smallcomputercentral.com

Related items

• SC523 - Printed circuit board on its own
• SC501 - Backplane
• SC502 - Power/reset card
• SC511 - Z80 SIO (serial I/O) card
• SC516 - Z80 processor card
• SC518 - Z80 CPU card
• SC519 - Z80 memory card
• Components, spares, and accessories

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 design is made with the permission of LiNC (designers of the Z50Bus).
• This product is designed for hobby use and is not suitable for industrial, commercial, or safety-critical applications.