How to figure out the byteorder only with one byte number?

Hi Tao,


On Mon, Feb 20, 2012 at 5:25 AM, Tao Jiang [off-list ref] wrote:

Hi:

Thank you all.

Take a byte number 0b00000001 for example
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ^ ? ? ? ? ? ? ^
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? high bit ? ? low bit

I used to think in a LE machine it will be stored as 0b10000000 low bit first

? ? ? ? ? ?^ ? ? ? ? ? ? ^

? ? ? ?low bit ? ? high bit

and in a BE machine will be 0b00000001 high bit first
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?^ ? ? ? ? ? ? ^
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? high bit ? ?low bit

not only the byteorder is different, but inside a byte is also different.

But actually they are the same, right?

yes they are same. In fact it is termed as 'byte' order not 'bit'
order. Hope this helps.

Thank you.



2012/2/20 Graeme Russ [off-list ref]:

quoted

On 02/20/2012 01:24 AM, Bernd Petrovitsch wrote:

quoted

On Sun, 2012-02-19 at 20:08 +0800, Tao Jiang wrote:
[...]

quoted

Is there some difference of the storge between BE and LE machine inside a byte?

No. At least TTBOMK there exists no such hardware.

Using SHL/SHR would tell you - SHL normally results in a multiply by 2, SHR
a divide by 2. If the byte was little endian, the results would be visa-versa

But I agree, I doubt there is any such hardware

Regards,

Graeme

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