I am receiving serial communication through the USB port to my Arduino (ATmega2560) by using the RX0 pin. In the receive function I want to compare the register that receives information `UDR0` with `unsigned char pckaffe[4]`. The data that is being sent through the USB port onto the Arduino comes from a pc and if everything works correctly, it should be sending unsigned char arrays, which is why I am comparing `UDR0` to `unsigned char pckaffe`. 

However at the if statement, the compiler is saying `Error ISO C++ forbids comparison between pointer and integer [-fpermissive]`

Why is that?

```
unsigned char pckaffe[4] = { 0x0C, 0x0A, 0x0F, 0x0E };

void USART_Receive(){
    while(!(UCSR0A & (1<<RXC0)) );
    if(UDR0 == pckaffe){
        PORTB ^= (1 << PB1);
    }
}

```