The external flash memory is an Adesto AT45DB641E (8MB).

The memory is split into several blocks:

  • 6MB reserved for weather data in Base64 format (i.e. the measured data), implemented as circulating memory (i.e. when memory is full, oldest data is overwritten with newer data)
  • 1MB reserved space for firmware update over the air
  • 1MB reserved for configuration and performance and behavior, including:
  • Station settings
  • APN tables (Access Point Names with MCC, MNC, user name and password)
  • Backup (serial number and similar important settings that normally are not changed)
  • Sensor image stores the configuration of the set of sensors connected to the iMetos. This info will be re-checked automatically every midnight so newly connected sensors will be detected and included in the logging. Manual update of this part of the memory can be done by pressing the reset button
  • Event history (information about communication network and internal parameters, detailed description is given later on in this manual)