Arduino for STM32

I am trying to communicate I2C between 2 STM32F103C8T6 but it does not work
Master code:
#include<Wire.h>
int z[16];
void setup()
{
Serial.begin(9600);
delay(50);
Wire.begin();
delay(50);
}


void loop()
{
Wire1.requestFrom(0x09, 16); //to receive 16-byte;
delay(50);
Serial.print("Slave data ...