Reading Digital Pins and Outputing on entire Ports
You have some coding errors.  You likely meant to write something like:

void loop() {
  x = digitalRead(inpin); //read the input pin
  if (x == HIGH) PORTB=B11111111; // if digital input is high, all Bport high
  if (x == HIGH) PORTC=B11111111; // if digital input is high, all Cport is high
  if (x != HIGH) PORTB=B00000000; // if digital input is low, all Bport is low
  if (x != HIGH) PORTC=B00000000; // if digital input is low, all Cport is low
}


Which could be simplified to:

void loop() {
if (digitalRead(inpin) == HIGH)
{
  PORTB=B11111111; // if digital input is high, all Bport high
  PORTC=B11111111; // if digital input is high, all Cport is high
}
else
{
  PORTB=B00000000; // if digital input is low, all Bport is low
  PORTC=B00000000; // if digital input is low, all Cport is low
}
}