This device driver controls MultiMediaCards (MMCs) and Embedded MultiMediaCards (eMMCs) by using the dedicated interfaces which are embedded in various MCUs.

This driver allows the updating and reading of data by calling user API functions. It is also an FIT module which supports our Firmware Integration Technology (FIT), so sample code for it is easy to integrate with user applications in combination with other FIT modules. Also, operation with DMAC or DTC transfer can be implemented by combining the driver with the DMAC FIT module or DTC FIT module. The driver is robust against mechanical vibration, so is suitable for industrial use.


  • Conforming standard
    JEDEC Standard JESD84-A441
    JEDEC Standard JESD84-B50
  • Bus interface
    MMC mode (1-bit/4-bit/8-bit) is supported
  • Number of MMC devices controlled
    One device/channel
  • Speed mode
    The Backward-compatible and High-speed mode are supported.
  • Microcontroller internal data transfer method
    Either software, DMAC, or DTC transfer can be selected
  • MCU-dependent portion
    Separate interface functions are provided for different target MCUs.
  • Memory capacity
    Media up to 2 GB is supported with byte access mode, and media over 2 GB is supported with sector access mode.
  • Memory control objects
    Only a user area is supported
    Boot area control is not supported

Release Information

Latest Ver.: V1.04
Released: Feb. 1, 2019

Target Devices

Additional Details

MultiMediaCard is a trademark of MultiMediaCard Association (MMCA)

Target Device & Product Lineup

Product Name MultiMediaCard / eMMC Driver for RX Family
Target Devices MultiMediaCard, eMMC
Target MCUs RX64M, RX65N, RX651, RX71M
Evaluation Board SD card slot or HMI Expansion Board Note is required. You can evaluate the driver on any of the following kits.

Note: Please purchase HMI Expansion Board.

The FAT32 formatter is capable of formatting eMMC devices with capacities up to 128 GB to have FAT32 file systems.

Obtaining the Product

Download: RX Family MMC Mode MMCIF Driver Firmware Integration Technology Rev.1.10 - Sample Code (ZIP)

Related Software

Please contact a Renesas sales representative or agent if using in combination with FAT file system.

M3S-TFAT-Tiny for the RX Family
Support is only for FAT12, FAT16, and FAT32.