For single source file 8051 projects the process is very simple. Compile your programs with the following command "sdcc sourcefile.c". This will compile, assemble and link your source file. Output files are as follows
SDCC can compile only ONE file at a time. Let us for example assume
that you have a project containing the following files:
foo1.c (contains some functions)
foo2.c (contains some more functions)
foomain.c (contains more functions and the function main)
The first two files will need to be compiled separately with the commands:
sdcc -c foo1.c
sdcc -c foo2.c
Then compile the source file containing the main() function
and link the files together with the following command:
sdcc foomain.c foo1.rel foo2.rel
Alternatively, foomain.c can be separately compiled as well:
sdcc -c foomain.c
sdcc foomain.rel foo1.rel foo2.rel
The file containing the main() function MUST
be the FIRST file specified in the command line, since the
linkage editor processes file in the order they are presented to it.
The linker is invoked from sdcc using a script file with extension
.lnk. You can view this file to troubleshoot linking
problems such as those arising from missing libraries.
Some reusable routines may be compiled into a library, see the documentation
for the assembler and linkage editor (which are in <installdir>/share/sdcc/doc)
for how to create a .lib library file. Libraries
created in this manner can be included in the command line. Make sure
you include the -L <library-path> option to tell the linker where
to look for these files if they are not in the current directory.
Here is an example, assuming you have the source file foomain.c
and a library foolib.lib in the directory mylib (if
that is not the same as your current project):
sdcc foomain.c foolib.lib -L mylib
Note here that mylib must be an absolute path name.
The most efficient way to use libraries is to keep separate modules
in separate source files. The lib file now should name all the modules.rel
files. For an example see the standard library file libsdcc.lib
in the directory <installdir>/share/lib/small.