----------------------------------------------------------------- |15 |14 |13 |12 |11 |10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |---|---|---|---|-----------|---|-------------------|-----------| | 1 | 1 | 0 | 0 |Rx REGISTER| 1 | OP-MODE |Ry REGISTER| ----------------------------------------------------------------- "Rx REGISTER" specifies a data or address register. If it's an exchange between a data register and an address register, this field define the data register. "Ry REGISTER" specifies a data or address register. If it's an exchange between a data register and an address register, this field define the address register. OP-MODE 01000->Exchange between data registers. 01001->Exchange between address registers. 10001->Exchange between data and address registers.