Beyond the Basics - BeagleBone - page 371

// usleep(100000); // sleep 100,000 uS
libsoc_gpio_set_level ( gpio_output , LOW );
// usleep(100000);
}
if ( gpio_output ) {
libsoc_gpio_free ( gpio_output ); // Free gpio request memory
}
return EXIT_SUCCESS ;
}
NOTE
In BoneScript and Python, we refer to the GPIO pins by the header position ( P9_14 , for ex-
ample). In libsoc , we refer to them by an internal GPIO number. Figure 5-18 shows how to
map from header position to GPIO pin. For example, P9_14 has GPIO_50 next to it. That
means libsoc needs to use GPIO 50 to interface with P9_14 .