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PurposeAims to design a heterogeneous embedded system with CPLD and microcontroller as co‐processors sharing a memory module.Design/methodology/approachThe system receives external analog input signal, which is applied to the PIC 16F73 microcontroller. Upon converting the data in to digital format using the on‐chip ADC, the PIC stores the digitized version in the SRAM (HCM 6264) chip. SRAM HCM 6264 has been used as a shared memory model, of which both the PIC and CPLD can access all the locations. Once the PIC passes controls to the CPLD, the further processing is carried out by the CPLD without any intervention of the PIC. This is a true example of co‐processing of the architecturally diversified computing modules from completely different vendors with totally different programming suits.FindingsThe board has been tested with IC temperature sensors and also found to be useful for sensor array applications involving three types of processing viz. analog (through instrumentation amplifier), real‐time digital (through microcontroller) and customized reconfigurable digital (with the CPLD).Practical implicationsThe system has several potential applications in avionics, military and robotic embedded systems, which have inherent real‐time constraints that need to be supported by the underlying hardware and driver programs.Originality/valueDiscusses the rare and unique combination of diversified processing core to build an embedded system.

As leading sensors of ambient conditions, temperature sensors act as important sensing devices. They are essential in a large variety of products. A variety of temperature sensors is available on the market to meet specific application needs. The most common include thermocouples, resistive temperature detectors (RTD), thermistors, and silicon‐based sensors. But of all of these temperature sensors, the thermistor is the only one that holds the esteemed position owing to its high sensitivity, accuracy and low cost. Temperature measurement systems utilizing thermistors are less expensive to produce because few additional components are required, especially in the present era of embedded systems. With the recent advances in manufacturing techniques, the drawbacks of conventional thermistors, like aging, interchangeability, unreliability etc., are almost eliminated. Booming demand for DVD players and portable communication appliances have pushed up the popularity of NTC thermistors. This article reviews the latest trends in thermistor manufacturing and the associated applications.