Consider the following program in MARIE assembly language. Complete the table detailing the RTN for next...

   

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Consider the following program in MARIE assembly language. Complete the table detailing the RTN for next 3 instructions only that will be executed including the content of registers PC, IR, MAR, MBR and AC in hexadecimal. Note the first instruction LOAD X is already filled. Note also that SKIPCOND instruction has no operands, therefore you can complete Fetch, decode and execute cycles only. Explain in one statement what is this program doing? (14 points) ORG 000 LOAD X Repeat, ADD One End, X, One, SKIPCOND 000 JUMP End STORE X JUMP Repeat STORE X HALT DEC -10 DEC 1 Instruction Load X Step Fetch Decode Get operand execute / AC = X / AC = X + 1 / if AC < 0 then PC = PC + 1 (skip) / Go to End / X = AC / Go to Repeat / Stop (end of program) RTN PC IR MAR MBR AC 000 0000 000 0000 0000 000 1008 000 0000 0000 001 1007 000 0000 0000 MAR PC IR M[MAR] PC PC + 1 Decode OPCODE IR [15-12]=0001 001 1007 000 => Load MARIR[11-0] MBR M[MAR] ACMBR 0000 0000 001 1007 008 0000 0000 001 1007 007 FFF6 0000 001 1007 007 FFF6 FFF6 Add One Skipcond 000 Jump End Fetch Decode Get Operand execute Fetch Decode Get Operand execute Fetch Decode Get Operand execute Consider the following program in MARIE assembly language. Complete the table detailing the RTN for next 3 instructions only that will be executed including the content of registers PC, IR, MAR, MBR and AC in hexadecimal. Note the first instruction LOAD X is already filled. Note also that SKIPCOND instruction has no operands, therefore you can complete Fetch, decode and execute cycles only. Explain in one statement what is this program doing? (14 points) ORG 000 LOAD X Repeat, ADD One End, X, One, SKIPCOND 000 JUMP End STORE X JUMP Repeat STORE X HALT DEC -10 DEC 1 Instruction Load X Step Fetch Decode Get operand execute / AC = X / AC = X + 1 / if AC < 0 then PC = PC + 1 (skip) / Go to End / X = AC / Go to Repeat / Stop (end of program) RTN PC IR MAR MBR AC 000 0000 000 0000 0000 000 1008 000 0000 0000 001 1007 000 0000 0000 MAR PC IR M[MAR] PC PC + 1 Decode OPCODE IR [15-12]=0001 001 1007 000 => Load MARIR[11-0] MBR M[MAR] ACMBR 0000 0000 001 1007 008 0000 0000 001 1007 007 FFF6 0000 001 1007 007 FFF6 FFF6 Add One Skipcond 000 Jump End Fetch Decode Get Operand execute Fetch Decode Get Operand execute Fetch Decode Get Operand execute

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