The original slidecaste is at http://youtu.be/eoLmiNusJUQ This presentation was made on Hardware Freedom Day at Moray House Trust in Georgetown Guyana, 20 April 2013. Mr Roger Nurse is a lecturer at the University of Guyana

1. B Y R O G E R N U R S E
Open Hardware and Logic
Circuits

2. Open Hardware
 Open source hardware consists of physical
artefacts of technology designed and offered by the
open design movement (wiki definition)
 The term usually means that information about the hardware
is easily discerned
 Hardware design (i.e. mechanical drawings, schematics, bills
of material, PCB layout data, HDL source code and integrated
circuit layout data), in addition to the software that drives the
hardware, are all released with the FOSS approach.

3. Focus
 Open hardware and logic circuits
 What are logic circuits?
 How are they useful?
 How are they designed?
 The effect of open hardware on logic circuits
 Hennessy and Patterson, MIPS and a strong case for open
hardware

4. What are logic circuits?
 Basis for the digital revolution
 An abstraction of basic Boolean logic constructs
 Circuits built upon implementations of the Boolean
AND, OR and NOT functions

5. How are they useful?

6. How are they designed?
 Simple digital circuits:
 Designed using simulating and implementation software
where chips are connected to build simple logic circuits

7. How are they designed?
 Complex digital circuits:
 Designed primarily using a hardware description language
(HDL). Most popular HDLs are VHDL and Verilog. More
complex and feature rich environments are used for design:

8. The Effect of Open Hardware on Logic Circuits
 Freely available chip designs and schematics
 Review of existing designs and possible
improvement
 Integration of existing designs into more complex
and feature rich systems
 Sky is the limit 

9. Hennessy and Patterson, MIPS
 Intel 4004, first commercial microprocessor and the
rise of the complex instruction set computer (CISC)
 Hennessy and Patterson, The birth of RISC and the
creation of MIPS
 Intel change of direction
 Imagine the potential benefits if the Intel processor
design information was readily available

10. Reference Material
 The elements of computing systems, Noam Nisan
and Shimon Schochken
 Computer Organization and Design, John Hennessy
and David Patterson
 Digital Design and Computer Architecture, David
Harris and Sarah Harris
 Open Source Software - Wiki

11. B Y R O G E R N U R S E
Questions and Comments