https://devzone.nordicsemi.com/f/nordic-q-a/44398/usage-of-1ulHello to everyone. I&#180;m trying to understand a code starting from the file of definition of pins of nRF52 PCA10040. In &quot;simple_hal.c&quot; there&#39;s a line like this: NRF_GPIO-&gt;OUTSET = 1UL &lt;&lt; i; in the hall_leds_init() function. To know the complete tasksen-USTelligent Community 13Wed, 06 Mar 2019 02:52:30 GMThttps://devzone.nordicsemi.com/thread/174411?ContentTypeID=1Wed, 06 Mar 2019 02:52:30 GMT137ad170-7792-4731-bb38-c0d22fbe4515:037f058f-8633-42b9-8512-d93c9e62149bJK0201<p>I see, so in this way, this 1 is compatible with any assignation?</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/174257?ContentTypeID=1Tue, 05 Mar 2019 13:05:54 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c0a992e8-b68d-48c7-b295-0017a9930917Susheel Nuguru<p>1UL just means 1 (unsigned long) and the width of which is architectural specific. Write like this is a good practice if you are writing a code for manipulating contents of registers so that the compilers do what you expect them to do.</p><div style="clear:both;"></div>