Accessing the nrf52820 pins

[MuRa]

Hello all

I am porting the code from the nRF52DK to the nrf52820, and so far so good, however, I am having a question, when configuring the TWI, will this get me the right PINS, for instance, according to the module manufacturer I should be accessing the P0.02 for SDA, while P0.08 for the SCL , this is my code:

void twi_init (void)
{
    ret_code_t err_code;

    const nrf_drv_twi_config_t twi_config = {
       .scl                = NRF_GPIO_PIN_MAP(0, 8), // ARDUINO_SCL_PIN,   //Add you SCL Pin Here
       .sda                = NRF_GPIO_PIN_MAP(0, 2), // ARDUINO_SDA_PIN,   //Add you SDA Pin Here
       .frequency          = NRF_DRV_TWI_FREQ_100K,
       .interrupt_priority = APP_IRQ_PRIORITY_HIGH,
       .clear_bus_init     = false
    };

    err_code = nrf_drv_twi_init(&m_twi, &twi_config, twi_handler, NULL);
    APP_ERROR_CHECK(err_code);

    nrf_drv_twi_enable(&m_twi);
}

This part works on the nrf52dk, for example where I am directly using the P0.27 and P0.26, however, the numbers 26 and 27 are simply used, as 26 and 27... 

hence my question, if I am accessing the pins correctly?

best.

[MuRa]

True that, I am looking at the el. schematics, ok, for example, how can someone enable or use the pin P0.20?

for example, I have tried to toggle the P0.14 with the nrf_gpio_pin_write(14, 1); //P(0.14)   / nrf_gpio_pin_clear(14); the led, so, now I would like to do the same with the P0.20?

Further more, I am trying to reach the pin F3, have a look at the attached pic, but not sure what M P stands for? 

Was hopping that the GPIO could be assigned via software ...

BEST. 

[MuRa]

Hi and thank you for your input!

I will try to answer your questions and elaborate what I had in mind.

nRF5xFanboy said:

On page 10 you will see the pins identifiers C4 & C5 (not handy labels for software people ;-)

Not sure what are you aiming here? btw SWDCLK, SWDIO , works ok, I can easily program the module. 

nRF5xFanboy said:

I only do not see any official TWI (i2c) pins coming out of the microcontroller / PAN1781 module.

I do not see it either, this is why I am looking at how to use the available GPIOs ... I think the GPIOs can be used for TWI...

nRF5xFanboy said:

It tells you that it is impossble to use theese pins as a normal TWI pins?

I am not trying to use the SWD..pins for the TWI...

nRF5xFanboy said:

unclear what you want with the TWI on the pan1781 route to the swd pins?

See above...

nRF5xFanboy said:

2nd question  "I have tried to toggle the P0.14 ....   now I would like to do the same with the P0.20?"
The the answer is simple 
nrf_gpio_pin_write(12, 1); // to make the gpio  level high (assume positive signal level.)
nrf_gpio_pin_write(12, 0); // to make the gpio  level low 

Thank you for that, it makes sense! 

nRF5xFanboy said:

The names are copied from the FT232R chip datasheet

Thanks for that , will have a look...

Thanks and the same!

Best.