The latest firmware version for the FRDM-K64F is: 0220 To check your firmware version:

• Open the DETAILS.TXT file if present.
• If not present, open the MBED.HTM file on your mbed microcontroller with a text editor

The below instructions explain how to upgrade your firmware.

Enter Bootloader Mode¶

1. Disconnect all power, external circuits and USB cables.
2. Press and hold the button marked RESET (circled in picture below)
3. Connect a USB cable as shown in the picture below
4. The drive should mount named BOOTLOADER
5. The reset button can now be released

When the FRDM-K64F is plugged in this way, it will appear as a disk called BOOTLOADER which you can simply copy the update file onto.

The latest mbed interface upgrade file for the FRDM-K64F is :

• 0220_k20dx128_k64f_0x5000.bin

2. Power cycle the board to update the firmware¶

After you have copied on the file onto the FRDM-K64F, simply unplug it, and plug it back in again, and the the USB disk will appear and an mbed disk.

3. Finished!¶

Firmware changelog¶

rev 0220 [ ... ]

• Update disc format and emulation for Mac Yosemite
• CDC and HID endpoints don't disconnect when programming via MSC
• Only erase sectors in target flash that are needed for the new program
• New details text file for information about the version and build

rev 0203 [ ... ]

• USBDevice stack patches for composite (CDC / MSC) race condition
• Flash algorithms created from new Kinetis flash driver source
• Mass-erase cannot be disabled and flash security enabled cannot be set (MSD programming only fails reserved bits for these conditions)
• UART serialization patch

rev 0202 [ ... ]

• Semihosting not enabled by default
• Updated mass erase sequence

rev 0201 [ ... ]

• Initial release