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µVISION: Why is the "Big Endian" checkbox greyed-out?

Information in this knowledgebase article applies to:

  • MDK v5.x
  • Cortex-M devices


I'm working with a Cortex-M4 based evaluation board. I found out in µVision Options for Target - Target - Big Endian option is greyed-out, as shown in this screenshot.

How can I enable this Big Endian option?


As summarized here (Data endianness: Little-endian or big-endian), unlike legacy ARM cores, the Cortex-M endianness of the device is permanently set by the silicon vendor and cannot be changed by user for a device.

Since your device is designed for and can only use little-endian, µVision prevents you from changing it.

See The device vendors Data Sheet or Reference Manual to find out if a chip is designed to use little-endian or big-endian ordering.


Last Reviewed: Tuesday, November 24, 2020

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