user4664: As opposed to PCINT (Atmel's Pin Change INTerrupt, INTx is arduino-compatible interupt)  In other words, does Software Serial use atmel's pin change or arduino falling interrupt?

user14737: SoftwareSerial uses PCINT.  AltSoftSerial uses INT0 or INT1, which has FALLING, RISING, CHANGE or LOW LEVEL options.  See Section 12.2, p. 71 of the Atmel ATmega328 spec, for example.

4664: <p>As opposed to PCINT (Atmel's Pin Change INTerrupt, INTx is arduino-compatible interupt)  In other words, does Software Serial use atmel's pin change or arduino falling interrupt?</p>
 14737: <p><code>SoftwareSerial</code> uses PCINT.  <code>AltSoftSerial</code> uses INT0 or INT1, which has FALLING, RISING, CHANGE or LOW LEVEL options.  See Section 12.2, p. 71 of the Atmel <a href="http://www.atmel.com/images/doc8161.pdf" rel="nofollow">ATmega328 spec</a>, for example.</p>
