> Ok David, > > Thank you and sorry, > I will studie the specific documentation. > I have made the modification in my sources and it is ok. > > Thank You >
It's no problem - and I hope I didn't sound too patronizing. Don't let it put you off asking more questions on this list if you want. It's not always easy to follow the documentation - I have also asked about things that were in documentation I hadn't noticed. But an understanding of "volatile" - when to use it, and when not to - is very helpful in embedded programming. mvh. David > > Bernard > > ____________________________________________________________________________ ____________________________ > > > David Brown a écrit: > > >Hi Bernard, > > > >This is a mistake many people make when they are new to embedded > >development, or new to using an optomising C compiler for embedded > >development. The code snippet "int x = 1; while (x) ; " tells the compiler > >to enter an infinite loop. You've already told the compiler what value "x" > >has - why should it bother re-reading it all the time? That's what > >optomisation is for - being smart and saving the processor some effort. > >What you need to do is declare your variable to be "volatile" - that tells > >the compiler the you really do want it to read the memory each loop. > > > >This is all explained in the documentation for the compiler - see > >http://mspgcc.sourceforge.net/doc_appendixE.html . You really should read > >through the documentation there before posting such questions, and even then > >it's polite to phrase your posts in the manner of "What I am I doing wrong" > >rather than "Perhaps there's a bug in the compiler" unless you are pretty > >confident that this is the case. > > > >And don't post in html - use plain text. > > > >mvh. > > > >David > > > > > > > > > > > >----- Original Message ----- > >From: Bernard MONDAN > >To: [email protected] > >Sent: Thursday, December 12, 2002 3:31 PM > >Subject: [Mspgcc-users] Perhaps a MSP GCC bug ?? > > > > > >Hi dmitry > > > >I think I have found a problem with the compiler. > > > >This is a shortcut to the problem : > > > >I have an interger that is set by a function, decremented by another (under > >interrupt) and tested by a third. > > > >I have tested this code : > > > >int xxxx; > > > >xxxx = 4; > > > >while( xxxx ) > > ; > > > >the generated code is : > > > > xxxx = 4; > > d8fa: 2f 42 mov #4, r15 ;subst r2 with > >As==10 > > d8fc: a2 42 7c 02 mov #4, &0x027c ;subst r2 with > >As==10 > > while(xxxx) > > d900: 0f 93 cmp #0, r15 ;subst r3 with > >As==00 > > d902: fe 23 jnz $-2 ;abs dst addr 0xd900 > > ; > > > >I think that at the address d902 the right code is jnz $-4 and not jnz $-2 > >beacause the others routines modifie the 0x027c address and not the r15 > >register. > > > > > >Please keep me informed about that. > > > >Thank you > > > > > >Bernard MONDAN > > > >HOMERIDER SYSTEMS > > > >[email protected] > > > > > > > >------------------------------------------------------- This sf.net email is > >sponsored by: With Great Power, Comes Great Responsibility Learn to use your > >power at OSDN's High Performance Computing Channel > >http://hpc.devchannel.org/ _______________________________________________ > >Mspgcc-users mailing list [email protected] > >https://lists.sourceforge.net/lists/listinfo/mspgcc-users > > > > > > > > > >------------------------------------------------------- > >This sf.net email is sponsored by: > >With Great Power, Comes Great Responsibility > >Learn to use your power at OSDN's High Performance Computing Channel > >http://hpc.devchannel.org/ > >_______________________________________________ > >Mspgcc-users mailing list > >[email protected] > >https://lists.sourceforge.net/lists/listinfo/mspgcc-users > > > > > > > > > > > > > ------------------------------------------------------- > This sf.net email is sponsored by: > With Great Power, Comes Great Responsibility > Learn to use your power at OSDN's High Performance Computing Channel > http://hpc.devchannel.org/ > _______________________________________________ > Mspgcc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/mspgcc-users > >
