This paper describes a case-study in intrinsic hardware evolution: the use of artificial evolution -- such as a Genetic Algorithm -- to design a circuit automatically, where each fitness evaluation is the measurement of a circuit's performance when physically instantiated in a real reconfigurable VLSI chip. The term `intrinsic' is used simply to indicate that the circuits are always tried out `for real' rather than in simulation [1]. However, my dictionary also gives the following meanings to the word: genuine, inherent, belonging to the point at issue. I suggest that the point at issue with intrinsic hardware evolution is to allow the genuine inherent physical behaviour of the silicon be used freely, rather than just using hardware as a fast implementation of an idealised simulation or designer's model. I aim to show this through an example.
The following sections consider the first ever [13] intrinsically evolved FPGA configuration in great detail -- there are interesting issues at every turn. The results speak for themselves, so I will save until later the underlying theory which motivated the rather unconventional approach taken. Then, in an extended discussion section, these ideas will be portrayed in the light of the experimental results that demonstrate their significance.