https://devzone.nordicsemi.com/f/nordic-q-a/61073/how-to-config-the-gpiote-and-timer-capture-mode-to-count-the-external-pulses-on-a-gpioHi, I am new to NORDIC dev and I find its ppi is really useful but also difficult to understand. Now my device may be connected the truck engine to count the engine speed(rpm) with a gpio. The engine generates a pulse on the GPIO and the device needsen-USTelligent Community 13Wed, 06 May 2020 11:01:12 GMThttps://devzone.nordicsemi.com/thread/248416?ContentTypeID=1Wed, 06 May 2020 11:01:12 GMT137ad170-7792-4731-bb38-c0d22fbe4515:f31e8dbb-4197-4896-b381-bda9267f1cc8Einar Thorsrud<p>Hi,</p> <p>I notice a few problems:</p> <ul> <li>You use the default timer configuration&nbsp;NRF_DRV_TIMER_DEFAULT_CONFIG as is, without doing any changes. Unless you have made changes in your sdk_config.h file, the default configuration for the timer driver is to use the timer in timer mode, not counter mode, which is what you want.</li> <li>You use NRF_TIMER_CC_CHANNEL0, but you should use the COUNT task to increment the counter in the timer (NRF_TIMER_TASK_COUNT).</li> </ul> <p>Looking quickly fixing those two issues should work. You could also refer to <a href="https://jimmywongiot.com/2019/10/03/how-to-count-gpio-pin-raising-falling-with-timer-counter-through-ppi/">this example</a>, which demonstrates exactly what you want to do (see the last part of&nbsp;timer_counter_with_gpio() <a href="https://github.com/jimmywong2003/nrf5-gpio-ppi-timer-counter/blob/master/ble_app_uart/main.c">here</a>.</p><div style="clear:both;"></div>