Looking at the transmitted byte after it has been properly reassembled won't tell you what order the bits arrived in, right?
Here is how I understand it: endianness refers to the ordering of the bytes within the larger word. The order of serial transmission of the bits within a byte is, by convention, least significant bit (LSB) first:
Most serial communications designs send the data bits within each byte LSB (Least significant bit) first. This standard is also referred to as "little endian."
from: Serial port - Wikipedia
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