Hi Michael, I guess I am spoiled by the linux irq thingies (which actually hides these details). If you are not writing a handler for Linux then you may have to do more asm work, as you/Ian mentioned. Sorry if I mislead you. Regards, Muthu On Tue, 28 Sep 2004, Michael Rausch wrote: > On Mon, 27 Sep 2004 20:20:37 -0700 (PDT), Muthukumar Ratty > <muthu@xxxxxxxxxx> wrote: > > >> 1) - Why is the #interrupt directive ignored by the PowerPC version of > >> GCC? > > > > What does it do? > > > Ooops! > The direcive is of course "#pragma interrupt". > I expected it to instruct the compiler to generate a "return from > interrupt" instruction at the end of the routine, instead of a "return > from subroutine". > This is what happens for the SH2. > The PowerPC actually has a "rfi" instruction, but the compiler silently > ignores the directive; the generated assembly code is the same and there > is no "rfi" at the end of the routine. > > >> 2) - Is it possible to write an interrupt service routine in pure C > >> language? > > > > Yes. > > > Without embedded assembly? > > >> 3) - Is there any prologue/epilogue code to be written for interrupt > >> service routines? > > > > No. Just the regular stuff, no blocking, quick, nested intr handling etc. > > > You mean that prologue/epilogue are the same for interrupt services > routines and normal functions? > > > Google? > > > I took the decision to ask the mailing list after about one month of > "googling" without finding really satisfying information (maybe there are > better keywords than: GCC, GNU, EABI, interrupt, Powerpc, and so on... ;-) > ). > > Thank you for your help! >
