SWI Example
===========
This directory illustrates an example SWI handler as a standalone project.
The files provided are:
main.c - contains the main() function, which installs the SWI vector in the
exception table, then calls some SWIs (0, 1, 2 & 3) via __swi()
ahandle.s - is the top-level SWI handler, written in assembler. It is entered
via the SWI vector of the execption table. Both ARM & Thumb SWIs
are identified and passed to chandle.c for processing.
chandle.c - is a second-level SWI handler, called from ahandle.s.
SWIs 0, 1, 2 & 3 execute some simple arithmetic.
swi.h - contains the definitions of __swi(0), __swi(1), __swi(2) & __swi(3).
__swi(3) has an associated __value_in_regs structure for returning
values in registers.
To build this example, use the CodeWarrior project file supplied (swi.mcp),
alternatively, to build from the command-line, use:
armasm -g ahandle.s
armcc -c -g -O1 main.c
armcc -c -g -O1 chandle.c
armlink ahandle.o main.o chandle.o -o swi.axf
This produces an ELF executable file (swi.axf) which can be loaded into an
ARM debugger.
For an overview of the principles of a SWI handler, see the ADS Developer Guide,
chapter 5.
