title: what does mean by __even_in_range(UCA0IV,0x08)
body: <p>I found this part from the example code for UART for MSP430FR57xx from TI.
  I don't understand what <code>__even_in_range(UCA0IV,0x08)</code> does mean?</p>
  
  <pre class="lang-c prettyprint-override"><code>#pragma vector=USCI_A0_VECTOR
  __interrupt void USCI_A0_ISR(void)
  {
      switch(__even_in_range(UCA0IV,0x08))
      {
      case 0:break;                             // Vector 0 - no interrupt
      case 2:                                   // Vector 2 - RXIFG
          while (!(UCA0IFG&amp;UCTXIFG));           // USCI_A0 TX buffer ready?
          UCA0TXBUF = UCA0RXBUF;                // TX -&gt; RXed character
          break;
      case 4:break;                             // Vector 4 - TXIFG
      default: break;
      }
  }
  </code></pre>