Q2.An 8255 chip is interfaced to an 8085 microprocessor system as an I/O mapped
I/O as show in the figure. The address lines A0 and A1 of the 8085 are used
by the 8255 chip to decode internally its thee ports and the Control register.
The address lines A3 to A as well as the signal are used for address
decoding. The range of addresses for which the 8255 chip would get selected is
Q6.An 8085 executes the following instructions
2710 LXI H, 30A0 H
2713 DAD H
2414 PCHL
All address and constants are in Hex. Let PC be the contents of the program counter and HL be the contents of the HL register pair just after executing PCHL. Which of the following statements is correct ?
Answer : Option CExplaination / Solution:
2710H LXI H, 30A0H ; Load 16 bit data 30A0 in HL pair
2713H DAD H ; 6140H ⟶ HL
2714H PCHL ; Copy the contents 6140H of HL in PC
Thus after execution above instruction contests of PC and HL are same and that is 6140H
Q7.The two numbers represented in signed 2’s complement form are P + 11101101 and Q = 11100110. If Q is subtracted from P, the value obtained in signed 2’s complement is