Microprocessors and Microcontrollers Mid - I, September - 2014

1.Single step command in DEBUG execution is enabled by _________ flag
  • Interrupt
  • trap
  • direction
  • sign
Answer: B
2.Segment registers are -bit in size.
  • 8
  • 16
  • 32
  • 20
Answer: B
3.AND SP, CX is in ______________addressing mode
  • Register
  • immediate
  • direct
  • indirect
Answer: A
4.The instruction used for terminating MASM program is
  • INT 3H
  • INT4H
  • INT2H
  • INT6H
Answer: A
5.CY, AC, P, S,Z,OV are the _____________flags of 8086
  • Status
  • control
  • general
  • special
Answer: A
6.What IC is known as programmable Peripheral Interface
  • 8255
  • 8253
  • 8254
  • 8251
Answer: A
7.8257 DMA controller has ___________________ channels
  • 4
  • 6
  • 2
  • 8
Answer: A
8.______________ internal register of 8259 PIC enable and disable IR lines
  • IRR
  • ISR
  • IMR
  • IPR
Answer: C
9.8086 MPU has the _________ bit memory mapping and ____________ bit IO mapping
  • 20, 16
  • 16, 16
  • 16, 20
  • 20, 20
Answer: A
10.Which port of 8255 operated in all the three modes
  • PA
  • PB
  • PC
  • ALL
Answer: A
11.If an address is represented as 1000:4500H, ______________is segment address and __________ is offset address.
Answer: 1000 , 4500
12.In the instruction MUL DX, op-code is ___________________
Answer: MUL
13.______________________ are the special purpose registers of 8086.
Answer: SI, DI, BP, SP
14.JMP is ______________________ branch instruction.
Answer: UNCONDITIONAL
15.DB stands for __________________________
Answer: DEFINE BYTE
16.In cascade 8259 can accept __________________ interrupt request.
Answer: 64
17.When D7 of 8255 is zero, the mode of control word register is _____________________
Answer: BIT SET RESET MODE
18.To make 32KB memory, ________________ number 8KB RAM iCs are used.
Answer: 4
19.DMA address register in 8257 is a _______________ bit register.
Answer: 16
20._____________ interrupt is used as a DOS function call.
Answer: INT 21H