<> <> <> <> Proposed Register Mux Specification: AR0 AR1 INDEX RAddr _ ARn, IBUFN, OPCODE<4>, K WAddr _ ARn', IBUFN, OPCODE<4>, K ARn' _ ARn, ARn +- 1, ARn +- INDEX, MUXBUS INDEX _ INDEX, MUXBUS MUXBUS _ IBUFN, OPCODE, K, D1<8>, AR0, AR1, INDEX D1 _ MUXBUS (one of the RD1Addrs) UpDate Options AR0 AR1 INDEX # +-1 +-1 NOP 2 +-1 NOP NOP 2 NOP +-1 NOP 2 +-INDEX +-INDEX NOP 2 +-INDEX NOP NOP 2 NOP +-INDEX NOP 2 MUXBUS NOP NOP 1 NOP MUXBUS NOP 1 NOP NOP MUXBUS 1 Total UCode Bits RAddr/WAddr = 4 UpDate = 4 MuxBus = 3  Total = 11