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WHAT IS A FIELD PROGRAMMABLE GATE ARRAY?
According to Xilinx ( http://www.xilinx.com/), the inventors
of the FPGA: “Field Programmable Gate Arrays (FPGAs) are
semiconductor devices that are based around a matrix of
configurable logic blocks (CLBs) connected via programmable interconnects.
FPGAs can be repro-
grammed to desired
application or func-
For engineers or
scientists who want to
make design decisions
at the hardware level,
an FPGA is a useful
Figure 2. Astable multivibrator
circuit diagram with LEDs.
Interfacing an FPGA
with an External Circuit
By Alexander DeForge
Let us begin with the question; “When is breadboarding
computer science?” The answer is, when you have a field
programmable gate array (FPGA). Building an astable
multivibrator and interfacing it with an FPGA was the
focus of this project. FPGA chips have low-level design applications. Interfacing an electronic circuit with an FPGA
allows for a simple and lightweight user interface during
the design process.
Figure 1. A workbench for this FPGA project; on the left is
the circuit, above is the FPGA, and in the background is a
resistor color band chart.