Re: [PIC] What to save in MCC18 interrupts? by olin

Harold Hallikainen wrote: > I'm having some trouble that I THINK is due to interrupts smashing data > in an MCC18 project with prioritized interrupts. The interrupt code is > all written in assembly with the exception of the C code that calls it > (below). That seems silly. If all the logic is in assembler, why do you need to create a C stub to call it? Interrupt code generally needs to be responsive, so you want to minimize cycles. At best the compiler won't put a lot of needless bloat in there. Interrupt entry and exit is well understood, and the compiler isn't going to come up with some magic optimization that the standard assembler entry/exit code doesn't already do. For a ready PIC 18 interrupt template, see my QQQ_INTR18.ASPIC module at http://www.embedinc.com/pic. You select a few things at the top with EQUs, and the appropriate template code gets selected. This includes a choice of single or high/low priority interrupts. All you have to do is insert the actual interrupt handling code. I've used this a bunch of times. ***************************************************************** Embed Inc, embedded system specialists in Littleton Massachusetts (978) 742-9014, http://www.embedinc.com