Question

Is it possible to implement conditional compiling in my source code so that it works for specific families?

Answer

Yes, our source code implements a series of define macros that can be leveraged to achieve this functionality. This technique is already used across multiple EMLIB modules to provide compatibility with multiple target devices. It can be useful in cases where a single source code file is to be used with multiple targets, but different functionalities are required.

It’s important to note that when building an MCU project with the Simplicity Studio IDE, the desired target architecture needs to be selected so that the relevant header files for the device are included in the project. The use of conditional compiling macros doesn’t override this functionality and it’s simply to allow a single source code file to be used across projects with different target architectures.

The necessary macros are found inside the header file containing the header file of the specific device usually located in the following path:

• <STUDIO_SDK_LOCATION>\platform\Device\SilionLabs<Desired device family>\Include
• e.g: \platform\Device\SiliconLabs\EFM32GG11B\Include\efm32gg11b820f2048gl192.h

Look for the “Part Family” define group. The relevant macros are highlighted in yellow in Figure 1 below:

Inside your source code, you need to implement a structure such as the following to determine a code snipped that will be conditionally compiled:

#if (defined(_EFM32_GIANT_FAMILY) && defined(_SILICON_LABS_32B_SERIES_1_CONFIG_1))
/* Conditionally compiled user code */
#endif

The same structure applies for Series 2 devices, only the “config” macro needs to be updated to the series 2 version. As for Series 0 devices, the “config” macro is not available, therefore, the “_SILICON_LABS_32B_SERIES_0” macro should be implemented instead. For example, for the Giant Gecko Series 0 family see the snippet below:

#if (defined(_EFM32_GIANT_FAMILY) && defined(_SILICON_LABS_32B_SERIES_0))
/* Conditionally compiled user code */
#endif

Attached to this KBA you can find a simple source code file that works with the SLSTK3700 and STK3701A development kits (Giant Gecko series 0 and 1 respectively). It’s a modified version of the “Blink” example and it integrates the macros to conditionally compile a different delay value for each board and to enable the DCDC converter in the STK3701A.