Guide to designing a device incorporating MEMS-based pico projection

Carlos Lopez

Over the last few years, millions of products incorporating pico projection have shipped, and developers are innovating new applications for this rapidly growing display category. Ideal applications for pico projection include near eye display, interactive digital signage, head mounted display, ultra short throw (UST) TV, standalone portable projectors and embedded projection in smartphones, tablets and laptops. New uses continue to emerge; for example, you might be able imagine a design for a thermostat using a display powered by gesture recognition or interactive touch.

Reed-Solomon Error Correction

C.K.P. Clarke

[Best paper on Reed-Solomon error correction I have ever read -- and it's from the BBC!] Reed-Solomon error correction has several applications in broadcasting,in particular forming part of the specification for the ETSI digital terrestrial television standard, known as DVB-T. Hardware implementations of coders and decoders for Reed-Solomon error correction are complicated and require some knowledge of the theory of Galois fields on which they are based. This note describes the underlying mathematics and the algorithms used for coding and decoding,with particular emphasis on their realisation in logic circuits. Worked examples are provided to illustrate the processes involved.

A Guide to Approximations

Jack G. Ganssle

Most embedded processors don’t know how to compute trig and other complex functions. Programming in C we’re content to call a library routine that does all of the work for us. Unhappily this optimistic approach often fails in real time systems where size, speed and accuracy are all important issues. The compiler’s runtime package is a one-size-fits-all proposition. It gives a reasonable trade-off of speed and precision. But every embedded system is different, with different requirements. In some cases it makes sense to write our own approximation routines. Why?