University of Ottawa, School of Electrical Engineering and Computer Science Question 4 (15 points) Four memory-reference...

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University of Ottawa, School of Electrical Engineering and Computer Science Question 4 (15 points) Four memory-reference instructions in the Basic Computer of the textbook's Chapter 5 are to be changed to the instructions specified in the following table, where "EA" denotes the operand's effective address. Symbol Opcode Symbolic designation NND 000 LSR 001 LSL 010 SKT 011 Symbol NND MEA] (ACA M[EA])' MEA] shr(M[EA]) In the following table, write down the necessary micro-operations (in RTL) to perform the execution phase of each instruction. Note that the execution phase of such type of instructions starts at T4. See figures 2 and 3 from Annex. LSR MEA]shi(M[EA]) If (MEA] mod 2-1) then PC Note 1. The value in AC should not be changed by the execution of any instruction, unless the instruction specifies a change in its content. To this extent, you can use TR to store the temporary content of AC. Note 2. Only msb and Isb of registers AC and E can be checked. CEC212a PC +1 Description in words Logic NAND of AC to memory Logical shift right memory content Logical shift left memory content Skip next 2 instructions if M[EA] is odd RTL Final Examination 2016 Comments LSL SKT University of Ottawa, School of Electrical Engineering and Computer Science Question 4 (15 points) Four memory-reference instructions in the Basic Computer of the textbook's Chapter 5 are to be changed to the instructions specified in the following table, where "EA" denotes the operand's effective address. Symbol Opcode Symbolic designation NND 000 LSR 001 LSL 010 SKT 011 Symbol NND MEA] (ACA M[EA])' MEA] shr(M[EA]) In the following table, write down the necessary micro-operations (in RTL) to perform the execution phase of each instruction. Note that the execution phase of such type of instructions starts at T4. See figures 2 and 3 from Annex. LSR MEA]shi(M[EA]) If (MEA] mod 2-1) then PC Note 1. The value in AC should not be changed by the execution of any instruction, unless the instruction specifies a change in its content. To this extent, you can use TR to store the temporary content of AC. Note 2. Only msb and Isb of registers AC and E can be checked. CEC212a PC +1 Description in words Logic NAND of AC to memory Logical shift right memory content Logical shift left memory content Skip next 2 instructions if M[EA] is odd RTL Final Examination 2016 Comments LSL SKT

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NND TR AC AC MEA TR TR NAND AC AC TR LSR AC MEA TR AC AC7 0 AC6 AC0 AC5 AC1 AC4 AC2 AC0 TR7 MEA AC L... View the full answer