Maximizing battery life on embedded platforms - Part 3. Computational and system efficiency

Maximizing battery life on embedded platforms - Part 3. Computational and system efficiency

Configure the tools correctly. The compiler and linker are unable to carry out even some basic optimisations unless they are fully aware of the target platform. Architecture version, core implementation, coprocessors and so on are all important. Write code sensibly to avoid unnecessary operations. On the ARM architecture 32-bit data types are efficient; in general 8-bit and 16-bit types, while they may occupy less storage, are less efficient to process. The packing and unpacking instructions and the SIMD operations in v6 and v7 of the architecture go some way to helping with this but be aware that, in the main, these instructions are not accessible from C as they do not map easily to C data types or operations. Algorithm selection is much more important. No matter what operation you are trying to carry out, there will almost certainly be not only multiple possible algorith...

Full article: http://www.edn.com/design/systems-design/4401022/Maximizi...