Hi Aashir javed,
What do you mean opensda bootloader mode? Do you mean FRDM K64 board enter bootloader mode, which will be a device named as "BOOTLOADER", and the enter method is: power off the board, press the reset button and hold on it, then power on the board with USB cable?
Or you mean the bootloader is a segment code which put in the K64 flash from address 0x00?
If just opensda bootloader mode, that is controlled by the on board K20 chip, not the K64 bootloader, you just need to press the reset button, it is OK.
But if you means the code in the K64, I highly suggest you refer to our KBOOT2.0 flash bootloader code, which can be downloaded from this link:
NXP_Kinetis_Bootloader_2.0.0 package
Wish it helps you!
If you still have question about it, please kindly let me know.
Have a great day,
Kerry
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