AN ENCODING TELEMETER FOR CLIMATIC TEMPERATURE MONITORING USING A SINGLE-CHIP MICROCONTROLLER

This paper discusses the baseband signal processing stages associated with a pulse code modulation (PCM) telemetry system designed for the r emote monitoring of climatic conditions. Based on an MC68HC11 single c hip microcontroller, the system features low power operation, an analo gue interface, data retention during power off and a serial communicat ion interface to a custom radio link or local computer/data logger. Th e operational performance is illustrated by way of test results obtain ed using a curve-matched thermistor to record environmental temperatur e. The telemeter described may be adapted to monitor other analogue vo ltage quantities.