In common TOS usage a structure with "Msg" in it is the payload
portion of a TOS_Msg or message_t structure that is transmitted
over the radio, or serial UART between the base-station and host.
Usually you can imagine the Msg being overlaid on the TOS_Msg.data[]
array set aside for user payload.
This particular "RssiMsg" contains a single field "rssi" so it's
a kinda redundant structure definition. As you say, "rssi" is a
16 bit signed quantity -- a "short int" on most 32-64 bit machines,
but most likely an actual "int" on the micro-controller itself.
The extra-added-complication is the "nx" part. This flags it to
the Nescc compiler as "network byte order" -- big-endian -- or
reversed byte order on just about every platform we use...
I think that was the question, if not, ask more.
MS
raoudha baklouti wrote:
> Subject:
> types
> From:
> raoudha baklouti <raoudha_baklo...@yahoo.fr>
> Date:
> Tue, 18 May 2010 12:06:07 +0000 (GMT)
> To:
> tinyos-help@millennium.berkeley.edu
>
>
> Hi,
> I want to know the meaning of
>
> typedef nx_struct RssiMsg{
> nx_int16_t rssi;
> }RssiMsg;
>
> is the meaning is that a variable RssiMsg that is stored in a byte
> arrays, have an attribute rssi that is a short int (nx_int16_t)
>
>
>
>
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