Adapter 28C256

What is it?

A complete kit for an Atmel 28C256 EEPROM adapter. (Does NOT include the Atmel 28C256 chip.)

Kit comprises:

• 1× PCB
• 1× 47KΩ Resistor
• 2× 14-way header
• 1× 4-way DIP switch
• 1× 28-pin DIL socket

Why did I make it?

When developing programs for the 65C02 SBC, I was forever programming EPROMs and then having to UV-erase them for any program changes. This adapter lets me program an Atmel 28C256 EEPROM and then make the SBC see it as a 27C256 EPROM. Switching between program mode and read mode is simply a matter of flicking a couple of DIP switches — no UV lamp required.

What makes it special?

A very simple and useable design.

Switch Settings

Switches	Mode
1 & 4 ON, 2 & 3 OFF	Program mode — Read and Write (28C256 EEPROM)
1 & 4 OFF, 2 & 3 ON	Run mode — Read only (emulates 27C256 EPROM)

Images