Register and Data manipulation // EXX (EXchange all)
Each 2-byte value in register pairs BC, DE, and HL is exchanged with the 2-byte value in BC', DE', and HL', respectively.
If register pairs BC, DE, and HL contain 445Ah, 3DA2h, and 8859h, respectively, and register pairs BC’, DE’, and HL’ contain 0988h, 9300h, and 00E7h, respectively, then upon the execution of an EXX instruction, BC contains 0988h; DE contains 9300h; HL contains 00E7h; BC’ contains 445Ah; DE’ contains 3DA2h; and HL’ contains 8859h.