A simple C library for accessing an MCP23S17 port expander.
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tompreston Merge pull request #10 from Robertof/various-fixes
Update to v0.3.3: support for installing the library, README.md fixups and additions
Latest commit f65a5e2 Jul 27, 2015



A simple library for accessing the MCP23S17 port expander through SPI.


To build the library, use:

$ make

Install the library to /usr/local using:

$ make install

To test the library, compile and execute the example program:

$ make example
$ ./example

Another example program, using interrupts, is available. Build with:

$ make interrupt_example
$ ./interrupt_example


See example.c and interrupt_example.c for ideas on how to use.

Compile your software with the following flag:


You can specify the path of the library manually, using:

-I/path/to/headers -L/path/to/libmcp23s17 -lmcp23s17


An online version of the documentation is available at http://piface.github.io/libmcp23s17.

Build it with (assuming that you are in the directory of the cloned repository):

$ cd docs/
$ doxygen libmcp23s17-doc.conf

To view as HTML, point your browser to docs/html/index.html.

To view as PDF:

$ cd latex/
$ make

The pdf is called refman.pdf.