//Master (Attiny45)
#include <TinyWireM.h>
#define slave1 (1)

void setup() {
  TinyWireM.begin();
}

  byte x=0;
void loop() {
  TinyWireM.beginTransmission(slave1);
  TinyWireM.send(1);
  TinyWireM.endTransmission();
  delay(1000);
  
  TinyWireM.beginTransmission(slave1);
  TinyWireM.send(0);
  TinyWireM.endTransmission();
  delay(1000);
  
 
}