https://devzone.nordicsemi.com/f/nordic-q-a/16949/is-there-any-reason-this-simple-gpio-timing-should-be-much-faster-with-sdk-11-0I&#39;ve got an application that does a lot of nRF51822 GPIO wiggling and the timing needs to be controlled. In one spot I simply set a pin high then low like this: nrf_gpio_cfg_output(5); nrf_gpio_pin_set(5); nrf_gpio_pin_clear(5); I&#39;ve ensureden-USTelligent Community 13Mon, 10 Oct 2016 07:52:40 GMThttps://devzone.nordicsemi.com/thread/64985?ContentTypeID=1Mon, 10 Oct 2016 07:52:40 GMT137ad170-7792-4731-bb38-c0d22fbe4515:41644989-6558-452f-aee4-8a60771cdbd1Ole Bauck<p>These functions are inline functions. Inline instructs the compiler to attempt to embed the function content into the calling code instead of executing an actual call, see <a href="http://stackoverflow.com/questions/7762731/whats-the-difference-between-static-and-static-inline-function">this</a> thread. Depending on your project and compiler optimization, the functions may be three lines of assembly, or several. You should look at the generated assembly code as RK suggested. You can for example do this in the debug window.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/64986?ContentTypeID=1Sun, 09 Oct 2016 23:35:10 GMT137ad170-7792-4731-bb38-c0d22fbe4515:00cffb7b-82f5-4dcb-a97e-032d9a49275fRK<p>why don&#39;t you look at the generated assembler and see for yourself. You&#39;re not going to explain a difference of a couple of clock cycles without doing so.</p><div style="clear:both;"></div>