On Thursday 15 January 2009 04:15:14 Dave Hylands wrote: > Hi Lin (and Dennis), > > >> And the function ISR(USART1_RX_vect) in Linux saves even fewer > >> registers. > > > > The solution is to NOT call functions from within your ISR. That is > > just evil. Get your data in the ISR, put it in a mailbox or buffer and > > have a regularly scheduled function handle the details from outside the > > ISR. I like to use ring buffers to store data from an ISR. When using > > the ring buffer the ISR modifies the "write" pointer, not the read > > pointer and the processing function outside the ISR modifies the read > > pointer and not the write pointer. This means that those pointers don't > > need "push/popped" in the ISR either. > > And here's some code that implements such a ring buffer. As David > Kelly points out, as long as the index type is uint8_t, then nothing > special is required (which for this particular implementation means > that buffers upto 128 entries would be supported) > > <http://websvn.hylands.org/filedetails.php?repname=Projects&path=%2Fcommon% >2FCBUF.h&rev=0&sc=0> > > It's important that the queue be declared volatile (as myQ is in the > sample).
And I was just about to ask if someone could post some well tested code! :) Thanks. -- Daniel O'Connor software and network engineer for Genesis Software - http://www.gsoft.com.au "The nice thing about standards is that there are so many of them to choose from." -- Andrew Tanenbaum GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C
signature.asc
Description: This is a digitally signed message part.
_______________________________________________ AVR-GCC-list mailing list AVR-GCC-list@nongnu.org http://lists.nongnu.org/mailman/listinfo/avr-gcc-list
