AN3209 Datasheet, PDF (1/42 Pages) STMicroelectronics – Developing your M24LR64-R datalogger application for temperature acquisition

AN3209
Application note
Developing your M24LR64-R datalogger application
for temperature acquisition
Introduction
The M24LR64-R is a Dual interface EEPROM. Since it has both an 13.56 MHz ISO 15693
RFID and a 400-kHz I²C interface, the device is a good solution for RF-enabled sensors for
which ST has developed a reference design. One of the main benefits brought by the
M24LR64-R is that the sensor data can be accessed in read and write mode without
consuming any on-board power.
This application note presents a practical useful application for the M24LR64-R datalogger.
It describes an autonomous battery-powered datalogger able to record and store 64 Kbits of
temperature data using the M24LR64-R Dual interface EEPROM (I²C and RF). The
datalogger microcontroller is an STM8L101K3. It communicates with the M24LR64-R using
its serial interface and controls an STTS75 digital temperature sensor.
An on-board demonstration firmware, the M24LR64-R_Datalogger_application_firmware,
stored in the STM8L101K3 memory selects and controls the temperature acquisition
through a RFID reader connected by a USB cable to a PC.
The application is delivered with a PC software, the M24LR64-
R_Datalogger_application_software, to configure and control the datalogger, as well as
download and display the temperature values.
ST provides all the resources required to develop your own datalogger application and PC
software:
● Source files of the data logger firmware (M24LR64-
R_Datalogger_application_firmware): they allow implementing I²C communications
between the M24LR64-R, the STTS75, and the STM8L101K3.
● Source files of the PC software (M24LR64-R_Datalogger_application_software): they
control RF communications between the M24LR64-R and an RFID reader.
Basic information about the M24LR64-R, STTS75, and STM8L101K3 component
characteristics, as well as a description of the algorithms for the datalogger firmware and PC
software are provided in this document.
Reference documents
● M24LR64-R datasheet
● “M24LR64-R tool driver install guide” user manual (UM0863)
● “Using the M24LR64-R datalogger reference design” user manual (UM0925)
● “How to manage M24LR64-R data transfers from the I²C bus or an RF channel”
application note (AN3057)
● STM8L101K3 datasheet
● STM8L101 reference manual (RM0013).
● STTS75 datasheet.
The documents are available from http://www.st.com/dualeeprom.
April 2011
Doc ID 17419 Rev 2
1/42
www.st.com