It is needed with reading multiple bytes and increments the FIFO. From the datasheet:
In order to read multiple bytes, it is necessary to assert the most significant bit of the subaddress field. In other words, SUB(7) must be equal to 1 while SUB(6-0) represents the
address of first register to be read
0x80 = b10000000
Mark --OzzMaker.com --
