I went through this problem recently. Your slave needs two functions: one for sending and the other for receiving data.

// function: what to do when asked for data
void requestEvent() {
Wire.write(t); 
}

// what to do when receiving data from master
void receiveEvent(int howMany)
{Val = Wire.read();}

Here is a code that works both ways of i2c communication in a single code

Sending and receiving different types of data via I2C in Arduino

I went through this problem recently. Your slave needs two functions: one for sending and the other for receiving data.

// function: what to do when asked for data
void requestEvent() {
Wire.write(t); 
}

// what to do when receiving data from master
void receiveEvent(int howMany)
{Val = Wire.read();}

Here is a code that works both ways of i2c communication in a single code

Sending and receiving different types of data via I2C in Arduino

I went through the this problem recently. Here is a code that works both ways of i2c communication in a single code

Sending and receiving different types of data via I2C in Arduino

I went through this problem recently. Your slave needs two functions: one for sending and the other for receiving data.

// function: what to do when asked for data
void requestEvent() {
Wire.write(t); 
}

// what to do when receiving data from master
void receiveEvent(int howMany)
{Val = Wire.read();}

Here is a code that works both ways of i2c communication in a single code

Sending and receiving different types of data via I2C in Arduino