What is the difference of a SWI and a Hardwareinterrupt?
For example if code toggles a port which is connected to a IRQ.
This question is the essence of my formerly thread. Hope there will be some posetive echo. :-)
a SWI is a software interrupt; the instruction SWI (with optional parameter) causes the processor to branch to a special software handler. see your SWI.s file for details, and of course your documentation. a hardware interrupt often notifies the processor of a peripheral related event - a character coming in from a UART, for example - but has the same effect in the sense that the processor branches to a predetermined location. for the ARM9, this is 0x18, where the VIC is interrogated as to where the software should just next to handle the event.