Consider the instructions in the given figure and find the contents of the CPU registers - PC, MAR, MDR, IR, R1 and R2.

Consider an instructionADD R1 , R2. ( Add the contents of Register R2 to the contents of Register R1)Give the steps (micro operations) involved in the execution of an above given instruction.Answer:MAR ← PCMDR ← Mem[MAR]IR← MDRR1← R1+R2PC← PC+4

Consider an instructionADD R1 , R2. ( Add the contents of Register R2 to the contents of Register R1)Give the steps (micro operations) involved in the execution of an above given instruction.

Show the contents in hexadecimal of registers PC, AR, DR, IR, and SC of thebasic computer when an ISZ indirect instruction is fetched from memory andexecuted. The initial content of PC is 7FF. The content of memory at address7FF is EA9F. The content of memory at address A9F is 0C35. The content ofmemory at address C35 is FFFF. Give the answer in a table with five columns,one for each register and a row for each timing signal. Show the contents of theregisters after the positive transition of each clock pulse.170 CHAPTER FIVE Basic Computer Organization and Design

Select where the source operands are located for the following two LC-3 instructions:0001 111 010 0 00 0111010 010 110011110If the source operands are located in memory, also distinguish the addressing mode used to access that memory.  from memory using Base+Offset adressing mode   immediately from the instruction's address Correct!  directly from a register Correct Answer  from memory using Indirect addressing mode You Answered  from memory using PC-Relative addressing mode   immediately from the instruction

Assume the following shows the initial contents of the specified registers and memory locations:REGISTER CONTENTSR4 0101 0000 0110 0000R5 0011 0001 0000 0000R6 0010 1100 0001 0000ADDRESS CONTENTS0x5050 0011 0001 0010 00000x5051 0101 0000 0110 10110x5052 0111 0011 0000 1111Also assume the following LC-3 machine instructions are loaded into memory at addresses shown:0x5010 0110 101 110 0000100x5011 1010 100 001000000What is the effective address for each of the instructions above?(Enter your 16-bit answer in hex like the following example: 0x2A3F)A.)   first instruction above B.)   second instruction above