Hi,
We are using NCS v2.0.2 on nRF52840.
I have a question: what is the best practice to re-configure uart/gpio at runtime?
What we need:
1, Configure 2 IOs as UART TX/RX
2, After ready to sleep, disable UARTE to save power, reconfigure the RX pin as a GPIO, and wait for interrupt.
3, After new data coming from RX pin during sleep, the interrupt is triggered and wake up the system and then reconfigure IOs as UART TX/RX (no need to worry about losing data during wake-up, the protocol on uart have a re-send mechanism to cover that)
4, After data received/sent, ready to sleep and repeat step 2
There are a lot of related functions from different layers: Pin Control(Zephyr) / PRS(NCS) / nrfx_uart_* functions(nrf HAL) / using NRF_* registers directly
Which is recommended? Using one of them or a combination of several?
What I am planning to do:
a, set UARTE and GPIO in DeviceTree and set them as disabled
b, set pin control dtsi to set default/sleep mode of uart/gpio
c, During runtime,
In step 2, call
pm_device_action_run(uart_dev, PM_DEVICE_ACTION_SUSPEND);
nrfx_uarte_uninit(&uart);
pm_device_action_run(gpio_dev, PM_DEVICE_ACTION_SUSPEND);
gpio_pin_configure()
gpio_pin_interrupt_configure(dev, DT_GPIO_PIN(RX0_NODE, gpios), GPIO_INT_EDGE_BOTH);
in step 3, call
gpio_pin_interrupt_configure(dev, DT_GPIO_PIN(RX0_NODE, gpios), GPIO_INT_DISABLE);
pm_device_action_run(gpio_dev, PM_DEVICE_ACTION_RESUME);
nrfx_uarte_init()
pm_device_action_run(uart_dev, PM_DEVICE_ACTION_RESUME);
Regards,
Anthony Yuan
