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= Supoperator = | = Supoperator = | ||
Since there are [[Instructions (Computer Science)#Suboperator|free bits]] in ''NOT'', we can assign more sub operators as long as they take less than 3 registers. | Since there are [[Instructions (Computer Science)#Suboperator|free bits]] in ''NOT'', we can assign more sub operators as long as they take less than 3 registers. We choose the [[ASR]] (arithmetic shift right) operator. | ||
== Decoding suboperator == | |||
Remember that ''BNZ'' does not get processed by the ALU. ALU currently processes 3 operators. That means that the MUX in the ALU have an empty output (2^2 - 3 = 1) that we can assign our new suboperator to. | |||
To prevent an extra MUX, we simply convert the operator/suboperator signal (4 bits) into a 2 bit MUX selector signal. | |||
[[Category:Computer Architecture]] |
Latest revision as of 15:50, 15 April 2024
Supoperator
Since there are free bits in NOT, we can assign more sub operators as long as they take less than 3 registers. We choose the ASR (arithmetic shift right) operator.
Decoding suboperator
Remember that BNZ does not get processed by the ALU. ALU currently processes 3 operators. That means that the MUX in the ALU have an empty output (2^2 - 3 = 1) that we can assign our new suboperator to.
To prevent an extra MUX, we simply convert the operator/suboperator signal (4 bits) into a 2 bit MUX selector signal.