mraa/docs/mock.md

Mock platform

Mocking capability allows libmraa user to work with the library without any real hardware available. Enabling this requires library recompilation with architecture override (see Building section below). When mock is enabled, library simulates actual HW operations at the backend so that for the application it looks like a usual board. Being implemented at the backend, the functionality is available in all language bindings libmraa supports.

Board configuration

This feature is yet in the experimental mode and not all functionality is available. Right now we simulate a single generic board with GPIO (without ISR) and an ADC with 10 (std)/12 (max) bit resolution, which returns random values on read.

We plan to develop it further and all contributions are more than welcome.

See the table below for pin layout and features

MRAA Number	Pin Name	Notes
0	GPIO0	GPIO pin, no muxing, no ISR
1	ADC0	AIO pin, returns random value on read

Building

Generally all the building steps are the same as listed in the main building guide, you just need to set some specific CMake options.

Linux

To build under Linux, follow standard instructions, just make sure to set the -DBUILDARCH="MOCK" CMake option.

Windows

Mocking capability allows us to build and use libmraa under Windows. That helps if you e.g. don't want to leave your customary Windows-based Python IDE, but want to develop libmraa-based programs.

Building Node.js bindings was not yet tested under Windows as MSYS2 does not have a ready-made package. Java was not tested either.

Prerequisites

You'll need the following to build libmraa under Windows:

• MSYS2 basic installation

• Several additional packages, install them by running

  pacman -S cmake base-devel gcc git
  

Compiling

The procedure is conceptually the same as under Linux - you first need to run CMake with specific options to generate makefiles and then run make to build everything.

• Run MSYS2 shell (not a MinGW one)

• Clone the libmraa git repo (let's assume into /home/test/mraa/mraa-src dir)

• Create a build directory outside of the clone one (let's say /home/test/mraa/mraa-build)

• Run CMake, switching off unsupported options and enabling mock platform:

  cmake ../mraa-src/ -DBUILDARCH="MOCK" -DBUILDSWIGNODE=OFF -DENABLEEXAMPLES=OFF
  

• Make, install and test:

  make clean && make install && make test
  

  All tests should pass.

Note: To have autocompletion in Python IDE, just point it to MSYS2's Python and make sure to specify any additional paths pointing to site-packages dir with mraa module if IDE requires that ("Interpreter Paths" in PyCharm). With the above settings the module will be installed into /usr/local/lib/python2.7/site-packages and the libmraa itself - into /usr/local/bin.