Microprocessors and Interfacing Mid - II, November - 2014

1.The program which is executed during the interrupt is known as
  • Interrupt vector table
  • Interrupt serivce routine
  • Interrupt serivce program
  • Interrupt routine program
Answer: B
2.BIOS is a _______ which provides I/O services
  • Set of interrupt tables
  • Set of procedures
  • Same as interrupt vector table
  • All of these
Answer: B
3.8251 USART is used for
  • Serial to parallel data conversion
  • Parallel to serial data conversion
  • 8086 interfacing to serial data
  • All of these
Answer: D
4.MOV 45, #4FH MOV R0, 45H INC R0 MOV @R0, #30H What is the location value of R0 and the content at that place?
  • 45H, 4F
  • 50H, 30H
  • 30H, 50H
  • 50H, 45H
Answer: B
5.Timer1’s ______ mode is a hold count mode
  • Mode 2
  • Mode 3
  • Mode 1
  • Mode 0
Answer: B
6.Serial data is received by the DTE from the DCE through which one of these signals?
  • RxD
  • CD
  • RTS
  • CTS
Answer: A
7.Which of the following is an active-low chip select signal for enabling RD and WR operations of 8259A
  • INT A
  • CS
  • PS
  • EN
Answer: B
8.The 8051 is a
  • 16 bit microcontroller
  • 32 bit microcontroller
  • 8 bit microcontroller
  • 24 bit microcontroller
Answer: C
9.The ……………… directive is used to indicate the beginning address of the source program.
  • ASSUME
  • DB
  • ORG
  • END
Answer: A
10.Which of these modes is a standard UART mode ?
  • Mode 0
  • Mode 1
  • Mode 2
  • Mode 3
Answer: A
11.Total number of interrupt service routines handled by 8086 microprocessor are ____________
Answer: 256
12.The 8259A can be easily interconnected in a system of one master with up to eight slaves to handle up to _____________ priority levels
Answer: 64
13.Synchronous method transfers a _____________ at a time
Answer: Block of data(characters)
14.The IEEE-488 standard allows up to ____________ devices to be connected on a bus
Answer: 0-15
15.External hardware interrupts are ______________
Answer: INT0,INT1
16.While the CPU is executing a program, an interrupt breaks the normal sequence of execution of instructions, diverts its execution to some other program called __________
Answer: Interrupt Service Routine
17.____________ flag is set when there is a carry out of 3rd bit during addition or subtraction operation and otherwise cleared.
Answer: Auxilary carry
18._______________ is a software that converts the mnemonics or assembly language source Code in to the machine code.
Answer: Assembler
19.In ________________ mode of 8051, the direct address of the operand is specified in the instruction itself.
Answer: Direct Addressing
20._________________ consists of carry, auxiliary carry, overflow and parity flags.
Answer: Program status word