Microcontroller design advantages for portable computing

ARM processors have achieved wide recognition for their suitability for handheld computing applications, and a number of products already use these CPUs in discrete roles. The traditional route to further reducing costs and power consumption is integration-that is, integrating the peripherals with the CPU. The ARM7100, the first of a series of high integration portable computer microcontrollers, follows this route. It also incorporates innovative features that solve design, test, road map, and time-re-market issues. The ARM7100 resulted from a collaboration between Psion Software and ARM. Psion had specific requirements for CPU performance, peripheral integration, and low overall power consumption, including several power management features. Prior to the ARM7100, ARM had designed a number of high-integration parts, and ARM designers used this experience to develop new bus architecture ideas. ARM incorporated these ideas into the ARM7100 to produce a highly modular design, which benefited both the silicon designer and the product manufacturer. This article first describes the ARM7100 and then highlights key device features by describing two innovative products using this microcontroller-one from Psion and one from a new stare-up company, OptionExist.