Digital Electronics- The 8051 Microcontroller

Digital Electronics- The 8051 Microcontroller
31. When the 8051 is reset and the EA line is LOW, the program counter points to the first program instruction in the:
  • internal code memory
  • external code memory
  • internal data memory
  • external data memory
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32. The designs of a centigrade thermometer and a PWM speed-control circuit can be implemented by the 8051.
  • TRUE
  • FALSE
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33. What is the difference between the 8031 and the 8051?
  • The 8031 has no interrupts.
  • The 8031 is ROM-less.
  • The 8051 is ROM-less.
  • The 8051 has 64 bytes more memory.
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34. To interface external EPROM memory for applications, it is necessary to demultiplex the address/data lines of the 8051.
  • TRUE
  • FALSE
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35. The following command will copy the accumulator to the location whose address is 23H:
MOV 23H,A
  • TRUE
  • FALSE
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36. The special function registers can be referred to by their hex addresses or by their register names.
  • TRUE
  • FALSE
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37. The contents of the accumulator after this operation
MOV A,#2BH
ORL A,00H
will be:
  • 1B H
  • 2B H
  • 3B H
  • 4B H
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38. The following program will cause the 8051 to be stuck in a loop:
LOOP:     MOV A, #00H
     JNZ LOP
  • TRUE
  • FALSE
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39. Which of the following commands will copy the contents of RAM whose address is in register 0 to port 1?
  • MOV @ P1, R0
  • MOV @ R0, P1
  • MOV P1, @ R0
  • MOV P1, R0
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40. The statement CALL READ passes control to the line labelled READ.
  • TRUE
  • FALSE
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