SPI_Master_Example .. Where is SPI_MASTER_0_ENABLE defined?

[muhkuhns]

I went to so many references and definitions of variables and functions but I can't seem to find where is decided to use either spi_master_0 or 1.. where is this magic config file mentioned here:

• This example uses only one instance of the SPI master.

• Please make sure that only one instance of the SPI master is enabled in config file.

or what exactly does this do:

#if defined(SPI_MASTER_0_ENABLE)
    #define SPI_MASTER_HW SPI_MASTER_0
#elif defined(SPI_MASTER_1_ENABLE)
    #define SPI_MASTER_HW SPI_MASTER_1
#else
    #error "No SPI enabled"
#endif

It defines SPI_MASTER_HW SPI_MASTER_0 when SPI_MASTER_0_ENABLE is defined? But where is SPI_MASTER_0_ENABLE defined??? I can't seem to find it nowhere.

[RK]

err it's a define - it's defined in the project as .. a define, or if you're using a makefile, in the makefile as a define. In the armgcc example it's in the Makefile (although that defines both of them, incorrectly). In the arm projects it's in the uvproj file, again doubly defined and in iar it's in the ewp file which I guess is what IAR calls its project files .. and again both of them are defined.

[muhkuhns]

I was only familiar with something like: "#define constantName value".. But thanks to your answer I found this in the target options of keil..

SPI_MASTER_0_ENABLE BOARD_PCA10028 NRF51

so when I change the 0 to 1 the SPI_Master_1 is used.. got it.. a little.

[Susheel Nuguru]

In Keil defining a constandName in targetoptions is similar to giving gcc -DsomeDevineName at the compile options. This values are passed to the preprocessing of the compilation stage. You could overwrite these defines in the source and header files.

[Susheel Nuguru]

muhkuhns ,

could you please update this thread.