1.
void xxx() Interrupt a Interrupt function, xxx represents the user-defined function name, interrupt 0 is an essential part of the interrupt function, and 0 is the interrupt number
/INT0 Interrupt number 0
EX0 is the external interrupt 0 switch
IE0 External interrupt 0 interrupt request flag
IT0 Trigger mode of external interrupt 0, when IT0 = 1, it is valid for falling edge; when IT0 = 0, it is valid for low level
/INT1 Interrupt number 2
EX1 is the external interrupt 1 switch
IE1 External interrupt 1 interrupt request flag. . .
IT1 Trigger mode of external interrupt 1,. . .
TF0 timer/counter T0 overflow interrupt flag request bit
ET0 Timer counter 0 control bit
T0 interrupt number 1
TF1 timer/counter T1 overflow interrupt flag request bit
ET1 Timer Counter 1 Control Bit
T1 interrupt number 3
TI/RI Interrupt No. 4 Serial Port Interrupt