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The octal representation of an integer is $(342)_8$. If this were to be treated as an eight-bit integer in an $8085$ based computer, its decimal equivalent is

  1. $226$
  2. $-98$
  3. $76$
  4. $-30$
asked in Digital Logic by Veteran (59.6k points)
edited by | 1.7k views

1 Answer

+21 votes
Best answer
$(3\; 4\; 2)_8 = (011 \; 100 \; 010)_2 = (11100010)_2.$

If we treat this as an 8 bit integer, the first bit becomes sign bit and since it is "1", number is negative. 8085 uses 2's complement representation for integers and hence the decimal equivalent will be $-(00011110)_2 = -30.$
answered by Veteran (359k points)
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0

Sir, why haven't you considered 0 ( 011100010 ) as the sign bit? I calculated the answer as 226.

0
they said its 8 bit integer
+1
Yes, I missed it. Thanks
0
@arjun_sin, it is not mentioned anywhere in question, first bit will be signed bit, i am confused here when we consider 1st bit is signed bit and when we ignore 1st bit
+1
In this question they have mentioned 8bit integer in an 8085 therefore we are considering 8 bit from LSB to MSB, if nothing is mentioned then we have to consider it as a +ve number.
0
can uh tell me meaning of 8085 based computer,
0

https://en.wikipedia.org/wiki/Intel_8085 

Main thing is we have to take 8 bit from LSB to MSB 

0
@Arjun @ Arjun

Sir , why we are considering it as signed no?


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