How to get transmitter input using digital pins

Projects Programming
1

byte last_channel_1
unsigned long current_time, timer_1
volatile int receiver_input_channel_1

in setup function

PCICR |= (1 << PCIE0);
PCMSK0 |= (1 << PCINT0);

in loop function

ISR(PCINT0_vect){
current_time = micros();

//for Channel 1 input

if(PINB & B00000001){
if(last_channel_1 == 0){
last_channel_1 = 1;
timer_1 = current_time;
} }
else if(last_channel_1 == 1){
last_channel_1 = 0;
receiver_input_channel_1 = current_time - timer_1;
}

can anybody explain this code, i got it from internet

2

Does it compile?

Paul

3

can anybody explain this code, i got it from internet

Where is the rest of it ?

4

What is the code supposed to do?

What is the transmitter?

What sort of data is it transmitting?

(My crystal ball is very cloudy today)

...R