1-bit Microprocessor :: Overview
Project maintainers
Details
Name: icu
Created: Oct 15, 2006
Updated: Dec 20, 2009
SVN: No files checked in
Other project properties
Category: Processor
Language: VHDL
Development status: Alpha
Additional info:
Design done
WishBone Compliant: No
License: GPL
ICU - 1-bit Microprocessor
This project, written in VHDL, implements a microprocessor based on the Motorola MC14500B Industrial Control Unit (ICU). In addition to the basic emulation of the microprocessor, a 12-bit program counter and jump/branch logic have been added. There are also input and output registers to provide a complete microcontroller, suitable for a variety of real-world control applications.
From an educational perspective the ICU project should provide a useful insight into basic microprocessor operation as well as a practical introduction to circuit design using VHDL. While a "1-bit" microprocessor might seem almost useless in light of modern 8/16/32 and 64-bit architectures, the ICU is really quite capable of implementing logic control functions. The original MC14500B was designed to replace hard logic with a simple programmable sequencer targeting "ladder logic" applications where output decisions were based on simple boolean logic applied to the input.
In addition to the VHDL implementation, the project will provide an open source "assembly language" compiler written in C. The assembler will output straight binary and "S-record" formatted binary for prom programming.