Consider a computer that has a number of registers such that the three registers R0 = 1500, R1 = 4500, and R2 = 1000. Show the effective address of memory and the registers’ contents in each of the following instructions (assume that all numbers are decimal).

(a) ADD (R0)+, R2
(b) SUBTRACT - (R1), R2
(c) MOVE 500(R0), R2
(d) LOAD #5000, R2
(e) STORE R0, 100(R2)

Question

Consider a computer that has a number of registers such that the three registers R0 = 1500, R1 = 4500, and R2 = 1000. Show the effective address of memory and the registers’ contents in each of the following instructions (assume that all numbers are decimal).

(a) ADD (R0)+, R2
(b) SUBTRACT - (R1), R2
(c) MOVE 500(R0), R2
(d) LOAD #5000, R2
(e) STORE R0, 100(R2)

anonymous · Answer

i think this is a two-address and instruction set  as far as i know ,since only two registers are involved in each instruction  part a,b
(a)  ADD (R0)+, R2 meaning : R0= R0+R2 ,and no effective address of memory 
(b) SUBTRACT - (R1), R2 not sure what dose that -(R1) means but :
R1=R1-R2 
(c) (d) and (e) dose not make any sense to me sorry.
ps : please provide the source of this question :) because i recently read a book 
about this particular area of computer science and did'nt see anything like those instrucions