Hi,
The Cortex -M3 and Cortex-M4 processors are two of the products in the ARM Cortex-M processor family. The whole Cortex-M processor family is shown in following figure.
The Cortex-M3 and Cortex-M4 processors are based on ARMv7-M architecture.
So the startup files is suit for the K64.

Have a great day,
Ping
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