1.
Which is the microprocessor comprises:
Correct Answer
D. All of these
Explanation
The microprocessor comprises all of these components: register section, ALU, and control unit. The register section stores data and instructions temporarily, the ALU performs arithmetic and logical operations, and the control unit manages the flow of data and instructions within the microprocessor. Therefore, the correct answer is "All of these."
2.
What will be stored by register?
Correct Answer
A. Data
Explanation
The register will store data.
3.
Accumulator based microprocessor example are:
Correct Answer
C. A and B
Explanation
The correct answer is A and B because both Intel 8085 and Motorola 6809 are examples of accumulator-based microprocessors. These microprocessors have a dedicated register called an accumulator that is used for arithmetic and logical operations. The accumulator stores the intermediate results of calculations and is a key component in the execution of instructions in these microprocessors. Therefore, both Intel 8085 and Motorola 6809 meet the criteria of being accumulator-based microprocessors.
4.
A sets of registers can contain:
Correct Answer
D. All of these
Explanation
A set of registers can contain data, memory addresses, and results. Registers are small, high-speed storage locations within a computer's central processing unit (CPU) that hold data that is being actively used or manipulated. They can store data values, memory addresses that point to specific locations in the computer's memory, and also hold the results of calculations or operations performed by the CPU. Therefore, all of these options are correct and can be contained within a set of registers.
5.
There are primarily two types of register:
Correct Answer
C. A and B
Explanation
The correct answer is A and B because general purpose registers are used for a wide range of functions and can store any type of data, while dedicated registers are designed for specific tasks and have predefined purposes. Therefore, both types of registers exist and serve different purposes in a computer system.
6.
BCD stands for:
Correct Answer
A. Binary coded decimal
Explanation
BCD stands for Binary Coded Decimal. BCD is a coding scheme that represents each decimal digit with a 4-bit binary code. In BCD, each decimal digit is encoded separately, allowing easy conversion between binary and decimal representations. This coding scheme is commonly used in digital systems, particularly in applications where precise decimal arithmetic is required. BCD is not the same as Binary Coded Decoded, and it is not a combination of both options A and B. Therefore, the correct answer is Binary Coded Decimal.
7.
Which is used to store critical pieces of data during subroutines and interrupts:
Correct Answer
A. Stack
Explanation
During subroutines and interrupts, the stack is used to store critical pieces of data. The stack is a data structure that follows the Last-In-First-Out (LIFO) principle, meaning that the last item added to the stack is the first one to be removed. This makes it suitable for storing data temporarily during subroutines and interrupts, as it allows for efficient retrieval of the most recent data when needed. The stack is commonly used to store return addresses, function parameters, and local variables, ensuring the correct flow of execution and preserving important data.
8.
The process by which data will be submitted in the stack is:
Correct Answer
A. Push
Explanation
The correct answer is "Push" because when data is submitted in a stack, it is added to the top of the stack using the push operation. The push operation pushes the data onto the stack, increasing its size and updating the top pointer to point to the newly added element. This allows for the data to be stored and accessed in a Last-In-First-Out (LIFO) manner.
9.
Each memory location has:
Correct Answer
C. Both A and B
Explanation
Each memory location in a computer system has an address, which is used to uniquely identify it. The address allows the system to locate and access the contents of that particular memory location. Additionally, each memory location stores data or instructions, which are referred to as its contents. Therefore, both A (address) and B (contents) are present in each memory location.
10.
IP stands for:
Correct Answer
A. Instruction pointer
Explanation
IP stands for Instruction Pointer. In computer programming, an instruction pointer is a register that holds the memory address of the next instruction to be executed. It points to the location in memory where the next instruction resides. The instruction pointer is automatically incremented after each instruction is executed, allowing the program to progress sequentially through its instructions. Therefore, the correct answer is "Instruction pointer."
11.
The size of data bus in 8085 is:
Correct Answer
C. 8bit
Explanation
The size of the data bus in the 8085 microprocessor is 8 bits. The data bus is responsible for transferring data between the microprocessor and other devices or components in the system. In the case of the 8085, it can transfer data in 8-bit chunks at a time. This means that it can handle data in the form of 8-bit binary numbers, allowing for a wide range of values to be processed and manipulated by the microprocessor.
12.
Address bus size is:
Correct Answer
B. 16 bit
Explanation
The address bus size refers to the number of bits that can be used to address memory locations. In this case, the correct answer is 16 bit, which means that the computer system can address up to 2^16 (65536) different memory locations. This is a relatively small address space compared to larger address bus sizes like 32 bit or 64 bit, which can address much larger memory spaces.
13.
Data bus is:
Correct Answer
B. Bi directional
Explanation
A data bus is a communication pathway that allows the transfer of data between different components of a computer system. It can be either unidirectional or bidirectional. In the case of a bidirectional data bus, data can flow in both directions, allowing for two-way communication between components. This means that data can be both sent and received through the bus. Therefore, the correct answer is bidirectional.
14.
Address bus is:
Correct Answer
B. Uni directional
Explanation
The address bus is described as uni-directional because it only allows data to be transferred from the processor to the memory or input/output devices. It is used to transmit the memory address from the processor to the memory module, indicating the location where data needs to be read from or written to. The address bus does not allow data to be transferred in the opposite direction, making it a one-way communication path.
15.
In 8085, all the results are stored in:
Correct Answer
A. Accumulator
Explanation
In the 8085 microprocessor, all the results are stored in the Accumulator. The Accumulator is a special register that is used to store intermediate results and final results of arithmetic and logical operations performed by the microprocessor. It is also used as a source or destination operand in various instructions. The Accumulator plays a crucial role in data manipulation and processing within the 8085 microprocessor, making it the correct choice for storing results.
16.
In 8085, register pairs are:
Correct Answer
B. BC, DE, HL
Explanation
In the 8085 microprocessor, register pairs BC, DE, and HL are available. These register pairs are used for various operations such as storing memory addresses, holding data, and performing arithmetic calculations. The AB, CD, EF, and HM register pairs mentioned in the options are not valid register pairs in the 8085 microprocessor. Therefore, the correct answer is BC, DE, HL.
17.
When 9th bit will come, after any arithmetic operation, carry flag will be:
Correct Answer
A. Set
Explanation
After any arithmetic operation, the carry flag will be set when the result of the operation produces a carry or overflow. This means that the result is too large to fit in the designated number of bits. Therefore, the carry flag will be set when the 9th bit is encountered.
18.
In an arithmetic result, if even number of ones are present, which flag will be set?
Correct Answer
D. Parity
Explanation
In an arithmetic result, the Parity flag will be set if an even number of ones are present. The Parity flag is used to indicate whether the result of an operation has an even or odd number of set bits. If there are an even number of ones in the result, the Parity flag will be set to indicate that the result has even parity.
19.
Auxiliary carry will be set when:
Correct Answer
B. Carry will be passed from bit 3 to bit 4
Explanation
The auxiliary carry flag is set when there is a carry from the lower nibble (bits 0-3) to the upper nibble (bits 4-7) during arithmetic operations. In this case, the correct answer states that the carry will be passed from bit 3 to bit 4, which means that there is a carry from the 4th bit to the 5th bit. Therefore, the auxiliary carry flag will be set in this scenario.
20.
Z flag will be set when:
Correct Answer
B. Final result is all zeros
Explanation
The Z flag is a flag in computer processors that indicates whether the result of an operation is zero or not. In this case, the correct answer is "Final result is all zeros." This means that when the final result of an operation is all zeros, the Z flag will be set. This flag is important in conditional branching and decision-making within a computer program, as it allows the program to check if a certain operation resulted in zero and take appropriate action based on that.
21.
Addressing mode is:
Correct Answer
A. Opcode, Operand and Process
Explanation
The addressing mode refers to the way in which the processor accesses the operands for an instruction. In this case, the correct answer is "Opcode, Operand and Process." This means that the instruction includes the opcode (which specifies the operation to be performed), the operand (which specifies the data on which the operation is to be performed), and the process (which determines how the operation is carried out). This addressing mode is commonly used in many computer architectures.
22.
LDA 2050 - example of
Correct Answer
C. Direct mode
Explanation
The given correct answer, "Direct mode," suggests that LDA 2050 is an example of a direct mode. In direct mode, the operand of an instruction specifies the actual data to be operated on. This means that the address of the data is directly specified in the instruction itself. In the case of LDA 2050, it implies that the instruction is directly loading the data from memory location 2050.
23.
Example of immediate addressing mode is:
Correct Answer
C. MVI H, 23
Explanation
The given example of immediate addressing mode is "MVI H, 23". In immediate addressing mode, the data operand is directly specified in the instruction itself. Here, the instruction "MVI H, 23" loads the immediate value 23 into the H register. This means that the value 23 is immediately moved into the H register without the need for any additional memory access.
24.
Indirect register addressing mode is explained by:
Correct Answer
A. MOV A,M
Explanation
The given correct answer, "MOV A,M," suggests that the indirect register addressing mode is explained by the instruction "MOV A,M." In this mode, the content of the memory location pointed to by the register is moved into the accumulator. This instruction is used to access data stored in memory indirectly through the register. The other instructions mentioned, "MOV A,B" and "MVI A,09," do not demonstrate the indirect register addressing mode.
25.
MOV H,L stands for
Correct Answer
B. Content of L is coming to H
Explanation
MOV H,L stands for "Move the content of L to H". This instruction is used in assembly language programming to transfer the value stored in the L register to the H register. Therefore, the correct answer is "Content of L is coming to H".
26.
Implicit addressing mode's example is:
Correct Answer
C. CMA
Explanation
The given example demonstrates the use of the implicit addressing mode. In the instruction "CMA", the accumulator's contents are complemented. This instruction does not explicitly specify any operands or memory addresses. Instead, it operates on the implicit operand, which is the accumulator. Therefore, "CMA" is an example of the implicit addressing mode.
27.
STAX B/D represents:
Correct Answer
C. Store the content of A in a memory location, which is pointed by BC or DE register pair
Explanation
STAX B/D represents the instruction to store the content of register A in a memory location. The memory location is determined by the register pair BC or DE. This means that the value in register A will be stored in the memory location pointed to by either BC or DE.
28.
Load the content of memory location to A, which memory location is pointed by BC or DE register pair - Example of the above mentioned statement is:
Correct Answer
D. LDAX B/D
Explanation
The correct answer is LDAX B/D. This instruction is used to load the content of the memory location pointed by the BC or DE register pair into the accumulator (A). LDAX B is used when the memory location is pointed by the BC register pair, and LDAX D is used when the memory location is pointed by the DE register pair.
29.
INX H means:
Correct Answer
A. Increment HL pair by 01
Explanation
INX H stands for "Increment HL pair by 01". This means that the value of the HL register pair, which consists of the H and L registers, will be incremented by 01. The H register will not be incremented separately, it will only be incremented as part of the HL pair. Therefore, the correct answer is "Increment HL pair by 01".
30.
MVI M, 07 represents:
Correct Answer
B. Immediately store 07 to memory pointer M, which is pointed by HL pair
Explanation
The instruction MVI M, 07 is used to immediately store the value 07 to the memory location pointed by the HL pair. This means that the value 07 will be stored in the memory address specified by the contents of the HL register pair. This instruction is commonly used in assembly language programming to load a value into a specific memory location.
31.
ADC B means:
Correct Answer
B. Accumulator+Reg B+Carry
Explanation
ADC stands for "Add with Carry". In computer programming, it is an instruction that adds the values of the accumulator and register B, along with the carry flag. The carry flag represents the carry or overflow that occurs when adding two numbers. Therefore, the correct answer is "Accumulator+Reg B+Carry".
32.
CMP M means:
Correct Answer
A. Content of M will be compared with A
Explanation
The correct answer is "Content of M will be compared with A". This means that the value stored in register M will be compared with the value stored in register A.
33.
If carry is reset and zero is set, it proves:
Correct Answer
A. Content of accumulator and content of source will be same
Explanation
If the carry is reset and the zero flag is set, it means that there was no carry generated during the previous operation and the result in the accumulator is zero. This implies that the content of the accumulator and the content of the source are the same, as both have a value of zero.
34.
When 8 bit data will be compared with A, the mnemonics will be:
Correct Answer
C. CPI 02
Explanation
The correct answer is CPI 02. In this question, we are comparing an 8-bit data with A. The CPI instruction is used to compare an immediate 8-bit data with the contents of the accumulator (A). So, CPI 02 compares the value 02 with the contents of A. CMP B and CMP 02 are incorrect because they compare the contents of the accumulator with B and 02 respectively, rather than comparing an immediate value with A.
35.
RAL means:
Correct Answer
A. Individual bit will be shifted one bit left and D7 will go to carry and carry will come to D0.
Explanation
The correct answer is that individual bit will be shifted one bit left and D7 will go to carry, and carry will come to D0. This means that each bit in the binary number will be moved one position to the left, and the leftmost bit (D7) will be stored in the carry flag. The rightmost bit (D0) will then be replaced by the carry flag. This process is known as a right arithmetic shift and is commonly used in computer programming and digital logic operations.
36.
To do the AND operation with 8 bit data, mnemonics will be:
Correct Answer
C. ANI 09
Explanation
The given mnemonics are used to perform the AND operation with 8-bit data. The mnemonic "ANA B" performs the AND operation between the accumulator and the contents of register B. Similarly, the mnemonic "ORA B" performs the OR operation between the accumulator and register B. The mnemonic "ANI 09" performs the AND operation between the accumulator and the immediate data value 09. Lastly, the mnemonic "ORI 09" performs the OR operation between the accumulator and the immediate data value 09.
37.
LHLD 2000 means:
Correct Answer
B. Content of 2001 will go to H and content of 2000 will go to L
Explanation
The correct answer is "Content of 2001 will go to H and content of 2000 will go to L." This means that the content of memory location 2001 will be transferred to the H register, while the content of memory location 2000 will be transferred to the L register.
38.
DCX L means:
Correct Answer
C. Wrong mnemonics
Explanation
The correct answer is "Wrong mnemonics." This means that the mnemonic "DCX L" is not a valid or recognized instruction in the given context. The other options suggest different actions or explanations, but the correct answer indicates that the mnemonic itself is incorrect.
39.
ADD A means:
Correct Answer
D. Content of A will be summed with A
Explanation
The correct answer means that the content of A will be added or combined with itself. In other words, the value of A will be added to itself, resulting in a sum of the two values.
40.
LDAX H means:
Correct Answer
C. Wrong mnemonics
Explanation
The given correct answer is "Wrong mnemonics". This implies that LDAX H is not a valid instruction in the given context. It is likely that LDAX H is not a recognized mnemonic or opcode in the programming language or system being referred to. Therefore, the correct answer indicates that LDAX H is an incorrect or invalid instruction.