Peter Rabbitson wrote:
The only thing I still do not understand is why the frame control field is passed to me in inverse-BIT order (I understand the BYTE inversion on an intel system,
Actually, for 802.11, at least, the two bytes of the frame control field are *not* inverted on little-endian systems such as Intel systems (they're not the only little-endian systems - almost all Alpha systems are little-endian as well, although most non-x86 and non-IA64 systems are big-endian) - the low-order octet is transmitted first - see 7.1.1 "Conventions" in 802.11-1999, on page 34 (PDF page 50):
In figures, all bits within fields are numbered, from 0 to k , where the length of the field is k + 1 bit. The octet boundaries within a field can be obtained by taking the bit numbers of the field modulo 8. Octets within numeric fields that are longer than a single octet are depicted in increasing order of significance, from lowest numbered bit to highest numbered bit. The octets in fields longer than a single octet are sent to the PLCP in order from the octet containing the lowest numbered bits to the octet containing the highest numbered bits.
and this is of no concern since we mark the single low order byte with [0] and let the system figure out on its own what to pass us). Is it a general rule of some kind of "network bit order" that every octet will be fed to me with the highest bit starting first?
There isn't any general rule of that sort - in fact, in 802.11, the *least*-significant bit is transmitted first, at least in the original 802.11 (and probably in 802.11b and later versions) - see 14.3.3.1.1 "Transmit state machine", on page 156 (PDF page 172):
Each PSDU data octet is processed and transmitted lsb first and msb last.
And if this is so why a document like the pdf we are referring to would not list the correct b7 - b0 order in their frame control field...
The more interesting question is perhaps "so why do they sometimes list them in msb-to-lsb order, as in Table 1, and sometimes show them in lsb-to-msb order, as in Figure 13?" I don't know the answer to that - lsb-to-msb reflects the order in which they're transmitted, and msb-to-lsb reflects the order in which people think about them.
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