The Eurocom8052
What is it?
The design is based on Eltec's Eurocom-I or better, my remake of it.This version is equipped with the Intel 8052, or in fact, its Atmel variant the AT89S51. It is part of the MCS-51 family. It is not a processor but a microcontroller. A microcontroller can be considered as a small computer inside a single IC. Inside this IC you will find a CPU, ROM, RAM and I/O. Most probably a microcontroller is taking care of your keyboard: it reads the keys and sends the code for a pressed key to the computer.
The reason I designed this board is the simple fact that I have a 8052AH-BASIC and several AT89S51s laying around. This BASIC version is mentioned in the Wikipedia article.
The first Eurocom8052
In most cases I started with keeping the 6821 I/O ICs. That's what I did with the Eurocom8085 but then I decided to create the 8052 version starting immediatly with 8155s instead of the 6821s.The schematic
The board
The Eurocom8052C
When creating the Eurocom80552, I decided to ommit the two top DIN connectors for the simple reason I had no left-over pins to populate them. Then the idea struck to populate the place for the left connector with the female version of the Elektor bus. So you probably already guessed, I also created an 8052 version with the Elektor bus at the top left of the board but ommiting the second 8155 needed for the right DIN connector.The schematic
The board
The Eurocom8052D
I restored the second 8155 but replaced the original right DIN connector with a LPT port compatible 26-pin header.The schematic:
The board:
You can email me here.