Abstract: An internal self-test and status reporting system for an electrical device with a plurality of components, a power supply and a microcontroller or microprocessor. The self-test system powers on and off each component one at a time and measures an amount of current drawn by the component with an internal current sensor. The self-test system compares the measured amount of current drawn by the component with an expected, predetermined current value or range. The self-test system then reports whether the measured amount of current drawn by the component matches the expected, predetermined current value or is within the expected, predetermined current range. The self-test system reports the results of the self-test by generating a pattern of signals on a general purpose input/output (GPIO) line, displaying a message on a display of the device, or generating a sound with a speaker of the device.

Abstract: A GPS receiver engine is provided having a software interface between the GPS and local applications. The GPS manufacturer provides to the local manufacturer a GPS Chip Set that includes hardware components and software components. The hardware components can include an RF circuit and a processor. The software components can include an object code library and interface files that are used to interface with the local application software. The local manufacturer customizes its local application software to run with the software interface provided by the software components of the GPS Chip Set, stores the GPS software and the local application software into a memory system, and incorporates the RF circuit, processor and memory system into its GPS end product.