Correct use of NRF_LOG for display on Termite

RE: Correct use of NRF_LOG for display on Termite

JK0201 — Fri, 22 Feb 2019 04:46:51 GMT

I´ll try it.
Thank you very much for the support.

RE: Correct use of NRF_LOG for display on Termite

Jørgen Holmefjord — Wed, 20 Feb 2019 09:06:02 GMT

The SAADC example will give you a digital representation of a analog signal, if you want to measure anything between high (1) and low (0), this is the example you need to use.

If you want to read the digital state of a GPIO (high or low), you can use this example: devzone.nordicsemi.com/.../gpio.zip

By connecting P0.26 to either VDD or GND on the DK, the example will output 1 or 0.

RE: Correct use of NRF_LOG for display on Termite

JK0201 — Wed, 20 Feb 2019 01:22:39 GMT

No, It doesn´t work.
SAADC is an example to get analog voltages, right? And for digital ones, is there any example?

RE: Correct use of NRF_LOG for display on Termite

Jørgen Holmefjord — Tue, 19 Feb 2019 09:13:14 GMT

You should not set the voltage on a GPIO higher than VDD + 0.3V, as this may break the chip. See Absolute maximum ratings for more details. On the DK, VDD is typically between 2.8-3.0 V. Try connecting the GPIO to VDD on the DK and see if it reads 1.

If you want to measure analog voltages, you need to use the SAADC peripheral. See the SAADC example in the SDK for how to use it.

RE: Correct use of NRF_LOG for display on Termite

JK0201 — Tue, 19 Feb 2019 01:04:03 GMT

I just tried to raise the voltage to 3.5V, but it does not work. I also tried to directly connect a DHT11 temperature and humidity sensor with digital output to the P0.26 pin, but it still prints 0 in Termite. Do I need an extra configuration for being a digital sensor or should it work?

RE: Correct use of NRF_LOG for display on Termite

JK0201 — Mon, 18 Feb 2019 22:06:19 GMT

Ok, I understand.
So, I have to put like 3.5V to reach 1, right? because I´m feeding my circuit with 5V.
And, if GPIO only allows me to have 1 and 0, there´s an option to get the real value in voltage?

RE: Correct use of NRF_LOG for display on Termite

Jørgen Holmefjord — Mon, 18 Feb 2019 13:30:27 GMT

You can only read 1 and 0 from the GPIO. The Input high voltage is defined at 0.7 * VDD. If you apply 1 V to the pin, you will not go above this limit, and the state will be low.

RE: Correct use of NRF_LOG for display on Termite

JK0201 — Fri, 15 Feb 2019 23:11:34 GMT

int main(void)
{
    // Initialize.
    log_init();
    leds_init();
    timers_init();
    buttons_init();
    power_management_init();
    ble_stack_init();
    gap_params_init();
    gatt_init();
    services_init();
    advertising_init();
    conn_params_init();
	
	nrf_gpio_cfg_input(26, NRF_GPIO_PIN_PULLDOWN);
	uint32_t pin_state = nrf_gpio_pin_read(26);

    // Start execution.
    NRF_LOG_INFO("Blinky example started.");
	NRF_LOG_INFO("Pin state: %d", pin_state);
    advertising_start();

    // Enter main loop.
    for (;;)
    {
        idle_state_handle();
    }
}

I´m actually cheking the code with "ble_app_blinky" example, because all the configurations to use LOG are already set, but I can´t make it work. I adjusted the original code with my own lines (16, 17, 21) and only prints the message "Pin state: 0", no matter if I introduce up to 1V of power.

RE: Correct use of NRF_LOG for display on Termite

Jørgen Holmefjord — Fri, 15 Feb 2019 10:34:21 GMT

I see that you have not initialized the log module in your application. You need to add this header file to the top of main.c:

#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"

and these lines in start of main-loop:

uint32_t err_code = NRF_LOG_INIT(NULL);
APP_ERROR_CHECK(err_code);

NRF_LOG_DEFAULT_BACKENDS_INIT();

RE: Correct use of NRF_LOG for display on Termite

JK0201 — Thu, 14 Feb 2019 23:48:05 GMT

Hello Jorgen, thank you for answer.
I can compile the program now, but I can´t see anything in Termite. I´m using a sdk_config.h file from an example that doesn´t need SoftDevice (blinky / PCA100040 / blank).
The original config file didn´t has the NRF_LOG_ENABLED and NRF_LOG_BACKEND_UART_ENABLED lines, so I added them copying from another sdk_config.h file (ble_app_blinky / PCA100040 / s132), but only those two functions.
I need to copy all the NRF_LOG functions? like BAUDRATE and TEMP_BUFFER_SIZE?
My question is because I´m not sure I´m using the correct Baudrate to link with Termite.

RE: Correct use of NRF_LOG for display on Termite

Jørgen Holmefjord — Thu, 14 Feb 2019 09:08:48 GMT

Hi,

If you want to get the state of the pin, you need to read the pin and store its value to a variable. You can then pass the variable to NRF_LOG:

uint32_t pin_state = nrf_gpio_pin_read(26);
NRF_LOG_INFO("Pin state: %d", pin_state);

NRF_LOG use printf format to format the strings.

Best regards,
Jørgen

RE: Correct use of NRF_LOG for display on Termite

JK0201 — Thu, 14 Feb 2019 05:51:46 GMT

Correction about the mistake: isn't line 20, I'm talking about line 24.

RE: Correct use of NRF_LOG for display on Termite

JK0201 — Thu, 14 Feb 2019 00:32:41 GMT

I´m sorry, the first 4 lines are wrong. Please don´t pay attention to them.