3.6. Bit and Byte Ordering

As a configuration option, Xtensa processors support either big- or little-endian byte ordering, shown in Figures 3.2 and 3.3. Diamond Standard series processor cores are pre-configured as little-endian machines. Little-endian byte ordering stores a number’s low-order byte in the right-most byte location in memory and the high-order byte at the left-most byte location. (The least significant or “little” end comes first.) For example, a 4-byte long integer is stored using the little-endian format in a 32-bit memory word as shown in Figure 3.2.

Figure 3.2. Little-endian byte ordering for a 32-bit word.
Figure 3.3. Big-endian byte ordering for a 32-bit word.

Little-endian ...

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