Good, because a bitshift should be a bitshift no matter the endianess,
although some may run into {un}signed extension issues...MS Rémi Villé wrote: > 2009/8/4 Alan Marchiori <[email protected] <mailto:[email protected]>> > > On Tue, Aug 4, 2009 at 10:28 AM, Rémi Villé<[email protected] > <mailto:[email protected]>> wrote: > > Hi, > > > > I have implemented a basic aggregation using an array of byte in > network > > messages. > > Sensed values are on 16 bit so I need two entries in this array > to write one > > value, and I use bitwise shift operators to perform that. > > > > When I run the application in real mode the values received on > the PC are > > whatever, but they are good with TOSSIM. > > So I think bitwise shift operators haven't the same effect on the > PC CPU and > > the telosb one, maybe the endianness is not the same. > > > > I would like to know if it can be an explanation, if one > component could > > allow to use bitwise shift operators regardless the plateform. > > > > Thanks, > > > > Rémi > > > > Bitwise operations will depend on the endianness of the cpu for what > you are doing. If you want it to work correctly across different > platforms you could either detect the endianness somehow (google > search should help there) or I believe there is some define to detect > the platform being used; so you would detect TOSSIM or telosb and have > the correct code for each. > > With that said, I think you are going about this the hard way. TOS > already has this figured out (and solved) this sort of problem with > platform independent types. Chapter 9 of > http://www.tinyos.net/tinyos-2.x/doc/pdf/tinyos-programming.pdf has > more information. If you need more help, post the code in question. > > > Thanks for your help, but I shamefully admit that I just forgot to use > Par sensor instead of Demo one :( (On TOSSIM the data sensed were > randomly simulated but not in real mode). > > So there's no problem with endianness. > > > ------------------------------------------------------------------------ > > _______________________________________________ > Tinyos-help mailing list > [email protected] > https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help _______________________________________________ Tinyos-help mailing list [email protected] https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
