title: Addressing pins of Register in microcontrollers
body: <p>I'm working on Keil software and using LM3S316 microcontroller. Usually we address registers in microcontrollers in form of:</p>
  
  <pre><code>#define GPIO_PORTC_DATA_R       (*((volatile uint32_t *)0x400063FC))
  </code></pre>
  
  <p>My question is how can I access to single pin of register for example, if I have this method:</p>
  
  <pre><code>char process_key(int a)
  {  PC_0 = a ;}
  </code></pre>
  
  <p>How can I get PC_0 and how to define it?</p>
  
  <p>Thank you</p>