Description : Which of the following instruction perform the move accumulator to external RAM of 16bit address? a) MOV @ DPTR, A b) MOVX @ Ri, A c) MOV A, @ Ri d) MOVX @ DPTR, A
Last Answer : c) MOV A, @ Ri
Description : What instruction performs Compare immediate to indirect and jump if not equal. a) CJNE A, #data, rel b) CJNE Rn, #data, rel c) CJNE @ Ri, #data, rel d) CJNE A, data, rel
Last Answer : b) CJNE Rn, #data, rel
Description : Which of the following instruction perform jump indirect relative to DPTR a) JMP A+DPTR b) JMP DPTR c) JMP @A+DPTR d) SJMP A+DPTR
Last Answer : b) JMP DPTR
Description : Which of the following instruction is used to set bit port directly? a) SET P1.0 b) MOV P1.0, bit c) SETB P1.0 d) JB P1.0, bit
Last Answer : JB P1.0, bit
Description : Which of the following instruction is wrong a) INC DPTR b) MOV @DPTR, A c) MOV A, @A+DPTR d) DEC DPTR
Last Answer : d) DEC DPTR
Description : Which of the following instruction is of logical instructions? i) CPL A ii) JC rel iii) DA A iv) ANL A, Rn v) RR A vi) CPL bit a) i, v b) v, iii, I c) iv, ii d) v, iii, ii
Last Answer : c) iv, i
Description : When a subroutine is called, the address of the instruction following the CALL instructions stored in/on the a. stack pointer b. accumulator c. program counter d. stack
Last Answer : d. stack
Description : The contents of accumulator before CMA instruction is A5H. Its content after instructionexecution isa) A5H b) 5AH
Last Answer : b) 5AH
Description : In an 8085 microprocessor, the instruction CMP B has been executed while the contentsof accumulator is less than that of register B. As a result carry flag and zero flag will berespectively (A) set, reset (B) reset, set (C) reset, reset (D) set, set
Last Answer : (A) set, reset
Description : What is the Result of RR A instruction if accumulator contains 1000 0000. a) 0000 0001 b) 0000 0000 c) 0100 0000 d) 0000 0010
Last Answer : a) 0000 0001
Description : A group of bits that tell the computer to perform a specific operation is known as_______ A. Instruction code B. Micro-operation C. Accumulator D. Register
Last Answer : A. Instruction code
Description : What is the control unit's function in the CPU? a. To transfer data to primary storage b. to store program instruction c. to perform logic operations d. to decode program instruction
Last Answer : b. to store program instruction
Description : The content of the accumulator after the execution of the following 8085 assembly language program, is MVI A, 35H MOV B, A STC CMC RAR XRA B (A) 00H (B) 35H (C) EFH (D) 2FH
Last Answer : (D) 2FH
Description : Memory access in RISC architecture is limited to instructions a. CALL and RET b. PUSH and POP c. STA and LDA d. MOV and JMP
Last Answer : c. STA and LDA
Description : What are the functions of an accumulator?
Last Answer : The accumulator is the register associated with the ALU operations and sometimes I/O operations. It is an integral part of ALU. It holds one of data to be processed by ALU. It also temporarily stores the result of the operation performed by the ALU.
Description : Actual data processing operations are performed in the arithmetic logic section, but not in the …. Storage section of a processor unit a. Primary b. Accumulator c. Buffer d. Secondary
Last Answer : a. Primary
Description : A storage area used to store data to a compensate for the difference in speed at which the different units can handle data is a. Memory b. Buffer c. Accumulator d. Address
Last Answer : b. Buffer
Description : Which is used to store critical pieces of data during subroutines and interrupts: a. Stack b. Queue c. Accumulator d. Data register
Last Answer : a. Stack
Description : LA stands for: a. Load accumulator b. Least accumulator c. Last accumulator d. None of these
Last Answer : a. Load accumulator
Description : Accumulator based microprocessor example are: a. Intel 8085 b. Motorola 6809 c. A and B d. None of these
Last Answer : c. A and B
Description : In Microprocessor one of the operands holds a special register called: a. Calculator b. Dedicated c. Accumulator d. None of these
Last Answer : c. Accumulator
Description : The most common addressing techiniques employed by a CPU is a. immediate b. direct c. indirect d. register e. all of the above
Last Answer : e. all of the above
Description : What the Difference between accumulator and instruction register 8080?
Last Answer : Examples: /360: no accumulator 8080: A 6800: A and B 8086: AX ...
Description : The ___________ contains the address of the next instruction to be executed. a) IR b) PC c) Accumulator d) System counter
Last Answer : Answer: b Explanation: PC stands for program counter (It contains the address of the next instruction to be executed)
Description : The load instruction is mostly used to designate a transfer from memory to a processor register known as_________ A. Accumulator B. Instruction Register C. Program counter D. Memory address Register
Last Answer : A. Accumulator
Description : A basic instruction that can be interpreted by computer generally has ________ A. An operand and an address B. decoder and an accumulator C. Sequence register and decoder D. None of the Above
Last Answer : A. An operand and an address
Description : In microprocessor the next instruction to be executed is stored in a) Program Counter b) Stack Pointer c) Memory Pointer d) Accumulator
Last Answer : Ans: Program Counter
Description : The act of writing new data into register (1) is possible only when the register is an accumulator (2) is possible only when the register is an accumulator or instruction register (3) erases the previous contents of the register (4) is non-destructive to existing contents
Last Answer : is possible only when the register is an accumulator or instruction register
Description : If initial content of accumulator is 44 H, find out the new content of accumulator after execution of the instruction RR A
Last Answer : Contents of Acc will be 22H ( as RR A divides acc by 2)
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 : A single instruction to clear the lower four bits of the accumulator I 8085 assembly language is: ANI FOH
Description : How does the microprocessor differentiate between data and instruction
Last Answer : When the first m/c code of an instruction is fetched and decoded in the instruction register, the microprocessor recognizes the number of bytes required to fetch the entire ... will be considered as data & the byte after the data will be treated as the next instruction.
Description : Why do we use XRA A instruction
Last Answer : The XRA A instruction is used to clear the contents of the Accumulator and store the value 00H.
Description : Explain the different instruction formats with examples
Last Answer : The instruction set is grouped into the following formats • One byte instruction MOV C,A • Two byte instruction MVI A,39H • Three byte instruction JMP 2345H
Description : Mention the categories of instruction and give two examples for each category
Last Answer : The instructions of 8085 can be categorized into the following five • Data transfer MOV Rd,Rs STA 16-bit • Arithmetic ADD R DCR M • Logical XRI 8-bit RAR • Branching JNZ CALL 16-bit • Machine control HLT NOP
Description : What is an instruction?
Last Answer : An instruction is a binary pattern entered through an input device to command the microprocessor to perform that specific function
Description : Define instruction cycle, machine cycle and T-state
Last Answer : Instruction cycle is defined, as the time required completing theexecution of an instruction. Machine cycle is defined as the time required completing one operation of accessing memory, I/O or ... request. Tcycle is defined as one subdivision of the operation performed in one clock period
Description : Explain the difference between a JMP instruction and CALL instruction.
Last Answer : A JMP instruction permanently changes the program counter. A CALL instruction leaves information on the stack so that the original program execution sequence can be resumed.
Description : How many operations are there in the instruction set of 8085 microprocessor?
Last Answer : There are 74 operations in the 8085 microprocessor.
Description : CISC stands for: a. Complex instruction set computer b. Camper instruct set of computer c. Compared instruction set computer d. None of these
Last Answer : a. Complex instruction set computer
Description : RISC stands for: a. Reduced Instruction set computer b. Reduced Instruct set compare c. Reduced instruction stands computer d. All of these 107. DEC stands for:
Last Answer : a. Reduced Instruction set computer
Description : ISA stands for: a. Instruct set area b. Instruction set architecture c. Both a and b d. None of these
Last Answer : b. Instruction set architecture
Description : Which is not the main feature of DEC Alpha: a. 64 Bit RISC processor b. Designed to replace 32 VAX(CISC) c. Seven stage split integer/floating point pipeline d. Variable Instruction length
Last Answer : d. Variable Instruction length
Description : How many speed of 8088,8085,8086 microprocessor: a. 2.5 Million instruction per second b. 1.5 Million instruction per second c. 3.5 Million instruction per second d. 1.6 Million instruction per second
Last Answer : a. 2.5 Million instruction per second
Description : Which is most commonly measured in terms of MIPS previously million instruction per second: a. Microprocessor b. Performance of a microprocessor c. Assembly line d. None of thes
Last Answer : b. Performance of a microprocessor
Description : RISC stands for: a. Reduced Instruction Set Computer b. Reduced Intergraded Set Computer c. Resource Instruction Set Computer d. Resource Instruction System Computer
Last Answer : a. Reduced Instruction Set Computer
Description : CISC stands for: a. Complex Instruction System Computer b. Complex Instruction Set Car c. Complex Instruction Set Computer d. None of these
Last Answer : c. Complex Instruction Set Computer
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 : 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 : Interrupts which are initiated by an instruction are a. internal b. external c. hardware d. software
Last Answer : b. external