Communication between ATtiny85 to arduino due

Hi . I wont to do project that ATtint 85 read ultrasonic sensor when i tell him and send the information to arduino due . I thinking to use Communication that the ATtiny 85 send the information With his PWM pin and arduino due read whit the Analog pin . But it’s not working . If somebady can explain to me hwo to do this Communication good or have batter idea hwo i can send information between ATtiny 85 to arduino due or hwo to read from the ultrasinc information ( i dont wont the arduino to read the data Because he need to read 4 sensor and do alot of thinks . I Appreciate any help.