Why am I only receiving the first address byte? (I2C Protocol)

Question

Expecting the slave to ACKnowledge and return data, but it does not. This is my protocol. This is my Datasheet

The datasheet mentions \"The slave will answer by sending

Answer 1

Difficult to tell without having details of the i2c library that is being used, but the one thing I'd be checking first is the i2c_start(I2C_READ).

The i2c address provided in the datasheet is 0x5a as you've put in your macro. But the first byte also contains the read/write flag as the least significant bit. The i2c_start() function has to be putting 0xb5 onto the bus (i.e. (0x5a << 1) + 1 for a read)

If i2c_start() is not, then your slave device is not actually being addressed and so won't ack.