Introduction

This application note describes the implementation of a temperature logger, demonstrating the use of several peripherals of the tinyAVR® 1-series. The TWI peripheral is used to communicate with a Microchip AT30TSE digital temperature sensor. The asynchronous RTC module is used to generate a timestamp for each temperature measurement and the data is written to an SD card via an SPI interface using the ELM-Chan Petit FAT file system library.

The example code can be used with either an ATtiny817 Xplained Pro (ATTINY817-XPRO) or an ATtiny817 Xplained Mini (ATTINY817-XMINI) (with some modifications - see the Required Hardware chapter for more information), and an I/O1 Xplained Pro Extension Kit. It is possible to reuse parts of the code for other applications requiring SD card file system access, using the TWI module in Master mode, interfacing with an AT30TSE temperature sensor, or using the RTC to keep track of real time.