Firmware for an intelligent digital multimeter

Certain features of the design of a digital multimeter (DMM) that require intelligent firmware are reported, including high system throughput, measurement algorithms, and electronic calibration techniques. By combining a fast, standards-level-accuracy analog-to-digital (A/D) converter with intelligent DMM firmware in an embedded system, higher performance levels can be achieved. Achieving higher system throughput on the HP-IB (IEEE-488) interface by both quick setup times and high transfer rates is discussed. Extended capabilities, such as memory management, waveform digitizing, and digital AC techniques, are considered. The storage, initialization and protection of calibration constants, including how they are kept secure from erasure, are examined