Doubt with ATmega2560

Projects Programming
1

I am increasingly confused, the ATmega2560 datasheet says that the INT0 and INT1 are on pins 21 and 20, (PD0 and PD1) but the http://arduino.cc/en/Reference/AttachInterrupt, says it is the 2 and 3, after all what is the true.

Thank you
José Rodrigues

2

The pin number of the Mega chip and the pin numbers of the Mega board bear only a passing relationship. The board pin numbers are 2 and 3.

3

PaulS:
The pin number of the Mega chip and the pin numbers of the Mega board bear only a passing relationship. The board pin numbers are 2 and 3.

The pins 21 and 20 I Indicated, were the board of the chip are 43 and 44.
This is my confusion.

Thank you
José Rodrigues