IF an instruction that needs to be fetched is in physical me

IF an instruction that needs to be fetched is in physical memory location 389F2 and CS = 2700; (a) does the code segment range include it or not? (b) If not, what value should be assigned to CS if the IP must equal 1282?

Solution

a)IP has a minimum value of 0000H and a maximum value of FFFFH, the logical address range in this case is 2700:0000 to 2700:FFFF. This means that the lowest memory location of the code will be 27000H(27000+0000)
and the highest will be 36FFFH(27000+FFFF). The desired instruction is beyond these two limits, i.e. the code range does not include it.

b) To calculate the value of CS substract the IP from Physical address and right shift it.
389F2-1282=37770.

Right shift=3777
So the CS will be 3777