• compatible with Arduino UNO and compatibles (not compatible with Arduino Mega)
• supports SD, Micro SD and SDHC memory cards
  • with basic libraries max. 4GB cards work
• memory card selection by switch (on the SPI bus)
• uses I2C and SPI buses
• compatible with 3.3V and 5V logic levels
• real-time clock is based on the popular DS1307 RTC chip (on the I2C bus)
• battery: CR1220 (not included)
• operating voltage: 2.6-3.6VDC
• stackable (reserves pin D4 for chip select line)

Links