Your pack 'v' and pack 'n' arrange the bytes in reverse order - and unpack 'b*' just unpacks them both from the same end ... hence the bytes come out in the reverse order - but each byte is read in ascending bit order, in accordance with the 'b' template spec.

Where you're unpacking the \x12\x34, that's also correct. Both 'b*' and 'B*' read the bytes in the same order, but read those bytes from opposing ends.
I don't think there's any nybble-swapping. You've just got one byte that's read either as 01001000 or (reversed) 00010010 (depending upon the template) - and another byte that's being read as either 00101100 or (reversed) 00110100 (depending upon the template).

... I think ...

Cheers,
Rob

In reply to Re^4: Bit order in bytes by syphilis
in thread Bit order in bytes by geoffleach

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