New to ARM programming and specifically nrf51822.

[moenad]

I searched over the website, I couldn't find a good introductory documentation for programming the nrf51822, specifically the nrf51-dk. I have a transistor hooked to p0.01, I want to set that pin to high... first of all what's the function to call? It's clear how to set it as output from the examples but now to how change states of the GPIOs.. also what is really annoying is how do you map between the pin id (p0.01 and so on) and their respective pin numbers (0, 1, ...), if I want to set p0.01 as an output pin, should I use pin 1? or what? am I missing something?

[Stefan Birnir Sverrisson]

Hi

You could start with looking at this tutorial.

You could use the pin change interrupt example in the nRF51 SDK v8.1 for your experiment. You press button 1 and LED 1 is lid. LED 1 on the nRF51 DK is connected to pin 21, so if you connect your transistor to pin P0.21 you should see a reaction when you press button 1.

[Gabriel C.]

First check the schematic of nRF51822 to see which pin definitions you have. This one below is from nRF51822 Dev. Board R2:

After you define the pin like:

#define PIN1       1
#define PIN2       2

And you set it as output like:

nrf_gpio_cfg_output(PIN1);

Then you set it high like:

nrf_gpio_pin_set(PIN1);

Or low:

nrf_gpio_pin_clear(PIN1);

Hope it helps.

[HSA]

@Stefan Birnir Sverrisson,

Suggested example not running with SD110 with SDK8.1. (error: flash download failed cortex-M0)

Please suggest. Thanks

[Stefan Birnir Sverrisson]

Make sure you removed any other code on the device. Do that in e.g. nRFgo Studio by selecting the device and press the ERASE ALL button.

Check if there is an flashing algorithm selected for the project. Select KEil -> Options for target -> Debug tab -> Settings -> Flash Download tab. There should be selected nRF51xxx algorithm. If it is not present, press the Add button and find it in the list of algorithms. Also in the same location, make sure that "RAM for algorithm" -> Size field has value 0x2000

[Stefan Birnir Sverrisson]

Second thought. The pin change interrupt example does not use any softdevice, so just erase the chip and flash the example, don't flash any softdevice