This report outlines the design and implementation of a subsystem within the automated e-nose prototype, which is based on a CMOS Pixelated Capacitive Sensor (PCS) array. The objective of the e-nose prototype is to detect the presence and identify the type of volatile organic compounds (VOCs). A potential use case is to accommodate greenhouses with these e-noses to detect infestations in plants.
The subsystem presented in this report is tasked with programming the FRDM-MCXN947 development board to enable and improve communication and control between the PCS array and the microcontroller unit (MCU). In addition, the development board is also explored to investigate the feasibility of replacing currently used external modules with on-board peripherals. To achieve this, the CTIMER and SCTIMER are analyzed and implemented with the MCUXpresso IDE. The results showed that both of these peripherals have difficulties in simultaneously generating clock signals of different frequencies required for the communication protocol between the sensor and the MCU. However, the SCTIMER is capable of generating a differential clock, currently produced by the AD9552 external clock, though with lower signal quality.