An embedded system for the infrared cloud imager

Abstract

The Infrared Cloud Imager (ICI) is a ground-based thermal infrared imaging instrument, with a new version currently in development at Montana State University, to measure cloud cover statistics. The next-generation ICI design incorporates an embedded system for consolidating the controls and sensors for the system. Instead of having dedicated lines to each component of the system, only one connection is needed to the internal microcontroller, and then the microcontroller connects to all other components. The embedded system is capable of supporting digital sensors and controls, analog sensors, and peripherals that communicate serially. In addition, an Ethernet connection is used to communicate with the embedded system inside the ICI system enclosure. The MC9S12NE64 is a 16-bit microcontroller from the Freescale Microcontroller HCS12 family that is capable of supporting the ICI system peripheral devices and was selected for the embedded system. Firmware was developed for the embedded ICI control system that supports TCP/IP Ethernet communications, analog channels, digital channels, and serial communications, and a command set was developed for interfacing with the system peripheral devices. A software application was created to establish an Ethernet connection with the embedded system and test the system commands. A second software application was implemented to act as a serial device connected to the embedded system. The development board for the microcontroller was used to test the analog and digital channels. The software and development board were used together to demonstrate that the ICI embedded system is capable of providing access to all of the ICI system peripheral devices through a single Ethernet connection. The test results verify that the next-generation ICI design is able to successfully incorporate an embedded system for consolidating the controls and sensors for the system.