Which instruction of 8051 microcontroller is used for reading data from code memory? 

A) Mov B) MOVC C) MOVX D) XCH

1 Answer

Answer :

Mov

Related questions

Description : The 8051 microcontroller is of ___pin package as a ______ processor. a) 30, 1byte b) 20, 1 byte c) 40, 8 bit

Last Answer : c) 40, 8 bit

Description : The 8051 microcontroller is of ___pin package as a ______ processor. a) 30, 1byte b) 20, 1 byte c) 40, 8 bit d) 40, 8 byte

Last Answer : c) 40, 8 bit

Description : Draw the format of PSW register of 8051 microcontroller and explain the function of each bit.

Last Answer : 1. CY: Carry flag. This flag is set whenever there is a carry out from the D7 bit after an 8 bit addition or subtraction. It can also be set to 1 or 0 directly by instructions such as SETB C and ... the A register contains an odd number of 1s, then P=1. P=0 if A has an even number of 1s.

Description : State any four important features of 8051 microcontroller.

Last Answer : Features of 8051 microcontroller:  1) 8- bit data bus and 8- bit ALU. 2) 16- bit address bus - can access maximum 64KB of RAM and ROM. 3) On- chip RAM -128 bytes (Data ... 0 and Timer 1, two external hardware interrupts- INT0 and INT1, Serial communication interrupt for both receive and transmit.

Description : Draw and explain Internal port structure of Port 0 and Port 1 of 8051 microcontroller.

Last Answer : Port-0 can be configured as a normal bidirectional I/O port or it can be used for address/data interfacing for accessing external memory. When control is '1', the port is used for address/data ... is not able to sink the current the pin voltage may rise, leading to a possible wrong reading.

Description : Explain with sketch the interfacing of 4 ×4 matrix keypad with 8051 microcontroller.

Last Answer : Interfacing keypad Fig. shows how to interface the 4 X 4 matrix keypad to two ports in microcontroller. The rows are connected to an output port and the columns are connected to an input port. To ... key has been pressed, the next task is to find out which column the pressed key belongs to.

Description : Describe 8051 microcontroller as boolean processor.

Last Answer : * 8051 processor is a CPU that can perform some operation on a data and gives the output. * The 8051 processor contains a complete Boolean processor for single-bit operations. * The internal RAM contains 128 ... CLR C means clear the carry bit SETB 20h means set the memory bit with bit address 20h.

Description : List specifications of 8051 microcontroller.

Last Answer : 1) 8- bit data bus and 8- bit ALU. 2) 16- bit address bus - can access maximum 64KB of RAM and ROM. 3) On- chip RAM -128 bytes (Data Memory) 4) On- chip ROM - 4 KB ( ... 0592 MHz 9) Has power down and idle mode in microcontroller when no operation is performed. 10) Six interrupts are available.

Description : AVR microcontroller executes most of the instruction in _________________. A. Single execution cycle. B. Double execution cycle. C. Both A& B D. None of the above.

Last Answer : architecture of embedded system consists of

Description : Processors used in many microcontroller products need to be______ A. high power B. low power C. low interrupt response D. low code density

Last Answer : B. low power 

Description : In immediate addressing the operand is placed a. in the CPU register b. after OP code in the instruction c. in memory d. in stack

Last Answer : b. after OP code in the instruction

Description : In microcontroller and LCD interface which line will instruct the LCD that microcontroller is sending data? a) DB0 b) RW c) EN d) RS

Last Answer : d) RS

Description : Which of the following registers is used to keep track of address of the memory location where the next instruction is located? A) Memory address register B) Memory data register C) Instruction register D) Program counter

Last Answer : Answer : D

Description : Which of the following registers is loaded with the contents of the memory location pointed by the PC? A) Memory address registers B) Memory data registers C) Instruction register D) Program counter

Last Answer : Answer : C

Description : Any data and instruction entered in the memory of a computer is__________ A. Storage B. Output C. Input D. Information

Last Answer : C. Input

Description : The register which holds the address of the location to or from which data are to be transferred is known as_______ A. Instruction Register B. Control register C. Memory Address Register D. None of the Above

Last Answer : C. Memory Address Register

Description : The instruction fetch operation is initiated by loading the contents of program counter into the and sends _ request to memory: a. Memory register and read b. Memory register and write c. Data register and read d. Address register and read

Last Answer : d. Address register and read

Description : Copy of instruction in cache memory is known as: a Execution cache b. Data cache c. Instruction cache d. Allof these

Last Answer : c. Instruction cache

Description : Instruction formats contains the memory address of the a. Memory data b. Main memory Cc. CPU d. ALU

Last Answer : b. Main memory

Description : The length of instruction set depends on: a. Data size b. Memory size c. Both d. None

Last Answer : b. Memory size

Description : MIMD stands for: a. Multiple input multiple data b. Memory input multiple data c. Multiple instruction multiple data d. Memory instruction multiple data

Last Answer : c. Multiple instruction multiple data

Description : Which of the following registers is used to keep track of address of the memory location where the next instruction is located? a. Memory address register b. Memory data register c. Instruction register d. Program counter

Last Answer : Program counter

Description : Which of the following registers is loaded with the contents of the memory location pointed by the PC? a. Memory address registers b. Memory data registers c. Instruction register d. Program counter

Last Answer : Instruction register

Description : When the RET instruction at the end of subroutine is executed, a. the information where the stack is iniatialized is transferred to the stack pointer b. the memory address of the RET instruction is ... two data bytes stored in the top two locations of the stack are transferred to the stack pointer

Last Answer : c. two data bytes stored in the top two locations of the stack are transferred to the program counter

Description : Which of the following registers is used to keep track of address of the memory location where the next instruction is located? a. Memory Address Register b. Memory Data Register c. Instruction Register d. Program Register

Last Answer : d. Program Register

Description : Which of the following registers is used to keep track of address of the memory location where the next instruction is located? a. Memory address register b. Memory data register c. Instruction register d. Program counter

Last Answer : d. Program counter

Description : Which of the following registers is loaded with the contents of the memory location pointed by the PC? a. Memory address register b. Memory data register c. Instruction registers d. Program counter

Last Answer : c. Instruction registers

Description : Which of the following registers is used to keep track of address of the memory location where the next instruction is located? a. Memory address register b. Memory data register c. Instruction register d. Program counter

Last Answer : d. Program counter

Description : Which of the following registers is loaded with the contents of the memory location pointed by the PC? a. Memory address registers b. Memory data registers c. Instruction register d. Program counter

Last Answer : c. Instruction register

Description : Which of the following registers is used to keep track of address of the memory location where the next instruction is located? a. Memory address register b. Memory data register c. Instruction register d. Program counter

Last Answer : d. Program counter

Description : Which of the following registers is loaded with the contents of the memory location pointed by the PC? a. Memory address register b. Memory data register c. Instruction registers d. Program counter

Last Answer : c. Instruction registers

Description : Which of the following are 3 byte instruction set ? (a) MV 1A, 32 H (b) JMP 2085 H (c) MOV C, A (d) ADD B 

Last Answer : JMP 2085 H is 3 byte instruction set

Description : The Complement Accumulator (CMA) instruction of 8085 processor on execution affects a. Zero Flag b. Sign Flag c. Carry Flag d. None of the flags

Last Answer : B

Last Answer : In a generic microprocessor, instruction cycle time is exactly the same as the machine cycle time.

Last Answer : An instruction used to set the carry Flag in a computer can be classified as arithmetic.

Description : The least justifiable use of the results of a standardized reading test is to Options: A) identify areas of pupil deficiency B) evaluate the reading instruction programme. C) Serve as a basis for report card marks D) Serve as the basis for a parent conference

Last Answer : C) Serve as a basis for report card marks 

Description : In 8051,After reset the SP register is initialized to address________. a. 8H b) 9H c) 7H

Last Answer : c) 7H

Description : In 8051 an external interrupt 1 vector address is of ________ and causes of interrupt if ____. a) 000BH, a high to low transition on pin INT1 b) 001BH, a low to high transition on pin INT1 c) 0013H, a high to low transition on pin INT1 d) 0023H, a low to high transition on pin INT1

Last Answer : a) 000BH, a high to low transition on pin INT1

Description : SP of 8051 is of ___ wide and it is loaded with the default value of ___ after reset. a) 2 byte, 08H b) 8 bit, 07H c) 1 byte, 09H d) 8 bit, 06H

Last Answer : d) 8 bit, 06H

Description : In 8051 which interrupt has highest priority? a)IE1 b)TF0 c)IE0 d)TF1

Last Answer : a)IE1

Description : In 8051 which interrupt has highest priority? a)IE1 b)TF0 c)IE0 d)TF1

Last Answer : c)IE0

Description : Describe power down mode and ideal mode of 8051 with circuit diagram . which SFR is used to set these modes and draw the same.

Last Answer : IDLE MODE In the Idle mode, the internal clock signal is gated off to the CPU, but not to the Interrupt, Timer and Serial Port functions. The CPU status is preserved in its entirety, the Stack Pointer, ... t change on chip RAM PCON (Power Control Register) SFR is used to set these modes.

Description : State the alternate pin functions of port 3 of 8051.

Last Answer :  the alternate pin functions of port 3 of 8051 :

Description : Draw interfacing of 16 × 2 LCD with 8051 and state the function of EN and RS of LCD

Last Answer : Diagram: RS: RS is the register select pin. We need to set it to 1, if we are sending some data to be displayed on LCD. And we will set it to 0 if we are sending some command instructions ... the LCD to latch in the data present at the data pins. This pulse must be a minimum of 450ns wide.

Description : Describe serial communication in 8051. Explain the use of SCON register.

Last Answer : 8051 micro controller communicate with another peripheral device through RXD and TXD pin of port3.controller have four mode of serial communication.  1. Serial Data Mode-0 (Baud Rate Fixed) In this mode ... .0 Receive interrupt flag. Set by hardware halfway through the stop bit time in mode 1. 

Description : Draw the format of TCON register of 8051 and describe the function of each bit of it.

Last Answer : TCON: TIMER/COUNTER CONTROL REGISTER.BIT ADDRESSABLE  TF1 TCON. 7 Timer 1 overflows flag. Set by hardware when the Timer/Counter 1 Overflows. Cleared by hardware as processor ... 0 type control bit. Set/cleared by software to Specify falling edge/low level triggered External Interrupt

Description : Explain following instructions of 8051. (i) ADDC (ii) L CALL

Last Answer : (i) ADDC: The ADDC instruction adds a byte value and the value of the carry flag to the accumulator. The results of the addition are stored back in the accumulator. Several of the flag ... . Then the program counter is loaded with the new address and control is transferred to the subroutine. 

Description : Explain processes of interrupt enabling and disabling in 8051.

Last Answer : Interrupts are the events that temporarily suspend the main program, pass the control to the external sources and execute their task. It then passes the control to the main program where it had left off. ... interrupts. Its bit sequence and their meanings are shown in the following figure.

Description : Explain function of following pins of 8051 (i) Pin 31 (ii) Pin 29 (iii) Pin 21-28 

Last Answer : i) Pin 31-EA : It is and active low I/P to 8051 microcontroller. When (EA)= 0, then 8051 microcontroller access from external program memory (ROM) only. When (EA) = 1, then it access internal ... /Output, when external memory is interfaced, PORT 2 pins act as the higher-order address bus. (A8-A15)