Page 1 : 1. How are the bits of the register PSW affected if we select Bank - 2 of 8051?, PSW.5=0 and PSW.4=1, PSW.2=0 and PSW.3=1, PSW.3=1 and PSW.4=1, PSW.3=0 and PSW.4=1, 2. When 8051 wakes up then 0x00 is loaded to which register?, PSW, SP, PC, None of the mentioned, 3. 8051 series have how many 16 bit registers?, 2, 3, 1, 0, 4. What is the maximum delay generated by the 12 MHz clock frequency in accordance to an, auto-reload mode (Mode 2 ) operation of the timer?, 125 μ s, 250 μ s, 256 μ s, 1200 μ s, 5. What is the function of the TMOD register?, TMOD register is used to set various operation modes of timer/counter, TMOD register is used to load the count of the timer, Is the destination or the final register where the result is obtained after the operation of the, timer., Is used to interrupt the timer, 6. What is the clock source for the timers?, some external crystal applied to the micro-controller for executing the timer, from the crystal applied to the micro-controller, through the software, through programming., 7. How many bytes in 24 kilobytes?, 1024, 24576, 1000, None of these, 8. How many nibbles are 16 bytes?, 8, 4, 16, 32, 9. How many K in 1 meg?, 1024, 24576, 10000, None of these, 10. Which of the following is Read modify write instruction, ANL P0, CPL A, XRL R0, All of the above

Page 2 : 11. Which of the following is not an instruction of 8051 instructions?, arithmetic instructions, Boolean instructions, logical instructions, none, 12. DAA command adds 6 to the nibble if:, CY and AC are necessarily 1, either CY or AC is 1, no relation with CY or AC, CY is 1, 13. Which of the following instruction is used to set bit port directly?, SET P1.0, MOV P1.0, bit, SETB P1.0, JB P1.0, bit, 14. Let A= 55H then after execution of ANL A,0XFO A=_______, 05 H, 50H, 0FH, F0H, 15. Which out of the four ports of 8051 needs a pull-up resistor for using it is as an input or an output, port?, PORT O, PORT 1, PORT 2, PORT 3, 16. Which instruction is used to check the status of a single bit?, MOV A,P0, ADD, JNB PO.0, label, CLR PO.05H, 17. A program that is responsible for this conversion is known as ?, Compiler, Assembler, Interpreter, Interrupts, 18. Which directive is used to indicate the beginning of the address?, EQU, START, ORG, END, 19. Which Instructions used for complement the bit (bit —- NOT bit)?, CLR bit, CPL bit, SETB bit, COM bit, 20. JB bit, target Instructions used for?, jump to target if bit = 0 (jump if no bit), jump to target if bit = 1, clear bit (jump if bit, then clear), jump to target if bit = 1 (jump if bit), one of the above