General knowledgeAsked by Anonymous23 Oct 2026, 11:33 AM ISTUpdated
In one line
Some famous processors, like ARM and PowerPC, can work in both big-endian and little-endian modes — they are called bi-endian.
ARM architecture family — Family of RISC-based computer architectures ARM processors, found in most smartphones, are famous bi-endian CPUs. Image: Wikipedia
The rule
A bi-endian processor is a CPU that can switch between big-endian and little-endian ways of storing data in memory.
There is no formula here, just a definition.
Let's understand it simply
Imagine you are writing numbers on a piece of paper. You can write from left to right (like English) or right to left (like Hindi or Urdu). Computers store numbers in memory too, and the order of the bytes (smallest units) can be from left to right (big-endian) or right to left (little-endian). A bi-endian processor is like a person who can read and write both ways!
Big-endian vs Little-endian
Big-endian
Little-endian
Order of bytes
Most significant byte first
Least significant byte first
Example (0x12345678)
12 34 56 78
78 56 34 12
How it works
The processor has a setting (a bit or a pin) to choose the endianness.
When this setting is changed, the processor starts reading and writing data in the chosen order.
Software or the operating system usually decides which mode to use.
Some processors can even change endianness while running, for different tasks.
The story behind it
The idea of endianness comes from how computers store numbers. As computers became more connected, it was important for them to understand each other's data. Some companies made processors that could switch between both styles, making it easier to share data between different systems.
Where you see it in real life
ARM processors: Used in most smartphones and tablets. They can switch between big-endian and little-endian.
PowerPC processors: Used in older Apple Macs and some gaming consoles (like PlayStation 3). They are bi-endian.
MIPS processors: Used in some routers and embedded systems. Many models are bi-endian.
SPARC processors: Used in some servers. Some versions are bi-endian.
SuperH processors: Used in some Japanese electronics. Some models are bi-endian.
Why it matters
Data sharing: Bi-endian processors can easily talk to both big-endian and little-endian systems.
Software compatibility: Makes it easier to run the same software on different machines.
Networking: Internet protocols use big-endian, so bi-endian CPUs help in network devices.
Learning: Helps students and engineers understand how computers handle data.
Common mistakes
Thinking all ARM processors are always little-endian. (Most are, but they can be set to big-endian.)
Mixing up endianness with bit order (endianness is about bytes, not bits).
Believing x86 processors are bi-endian. (They are only little-endian.)
Remember it
ARM, PowerPC, MIPS, SPARC — these famous CPUs can switch byte order, so they are bi-endian.
Check yourself
Name two famous bi-endian processors.
ARM and PowerPC are both bi-endian.
Why are bi-endian processors useful in networking?
Because network protocols use big-endian, so bi-endian CPUs can handle network data easily.
Is an Intel x86 processor bi-endian? Why or why not?
No, x86 is only little-endian, so it cannot switch byte order.
Quick recap
Bi-endian processors can switch between big-endian and little-endian modes.
Famous bi-endian CPUs include ARM, PowerPC, MIPS, and SPARC.
Endianness is about the order of bytes in memory.
Bi-endian CPUs help with data sharing and compatibility.
