Tuesday, November 29, 2005
What are the different types of instruction formats?
i)Three address instructions ii) Two address instructions
iii) One address instructions iv) Zero address instructions.
What is a program counter?
Program counter is the register in the computer that keeps track of the instructions to be executed. It holds the next instruction to be executed.
What is implied mode?
The operands are specified implicitly in the instruction. For example : Complement accumulator
What is Immediate mode?
The operands are specified in the instruction itself. Instead of address it has the operand field
What is register mode?
When the address field specifies a processor register, it is said to be register mode instruction.
What is register indirect mode?
The instruction specifies a register in the CPU whose contents give the address of the operand in memory.
What is autoincrement or autodecrement mode?
In this the register content is incremented or decremented after or before its value is used to access memory.
What is effective address?
Effective address is defined to be the memory address obtained from the computation dictated by the given addressing mode. This normally adds the address given in register or memory location with a constant to find the resultant address.
What is direct address mode?
The effective address is equal to the address part of the instruction. The operand resides in memory and its address is given directly by the address field of the instruction.
What is indirect address mode?
The address field of the instruction gives the address where effective address is stored in memory. Control fetched the instruction from memory and uses its address part to access memory again to read the effective address.
What is relative address mode?
In relative address mode, the content of the program counter is added to the address part of the instruction in order to obtain the effective address.
What is indexed addressing mode?
The content of the index register is added to the address part of the instruction to obtain the effective address.
What is base register addressing mode?
The content of the base register is added to the address part of the instruction to obtain the effective address.
What are the types of instructions?
i. Data transfer instructions
ii. Data manipulation instructions
iii. Program control instructions
What is data transfer instruction? List them.
Data transfer instructions move data from one place to another without changing the data content. They transfer data between memory and processor registers, between processor registers and input or output, and between processor register themselves.
They include
i) Load ii) Store iii) Move iv) Exchange
v) Input vi) Output vii) Push viii) Pop
What are data manipulation instructions? What are the types?
Data manipulation instructions perform operations on data and provide the computational capabilities for the computer. They are of three types:
i. Arithmetic instruction
ii. Logical and bit manipulation instructions
iii. Shift instructions
What are arithmetic instructions? List them.
The four basic arithmetic operation are: addition, subtraction, multiplication and division. They are Increment, Decrement, Add, Subtract, Multiply, Divide, Add with carry, Subtract with Borrow, Negate
What are the status register bits?
Carry, Sign, Zero, Overflow (Briefly explain them)
What is a program status word?
The collection of all status bit conditions in the CPU is called program status word or PSW.
What are the types of Interrupts?
There are three major types of interrupts that cause a break in the normal execution of a program. They can be classified as:
i. External Interrupts
ii. Internal Interrupts
iii. Software interrupts ¶ 1:44 AM
i)Three address instructions ii) Two address instructions
iii) One address instructions iv) Zero address instructions.
What is a program counter?
Program counter is the register in the computer that keeps track of the instructions to be executed. It holds the next instruction to be executed.
What is implied mode?
The operands are specified implicitly in the instruction. For example : Complement accumulator
What is Immediate mode?
The operands are specified in the instruction itself. Instead of address it has the operand field
What is register mode?
When the address field specifies a processor register, it is said to be register mode instruction.
What is register indirect mode?
The instruction specifies a register in the CPU whose contents give the address of the operand in memory.
What is autoincrement or autodecrement mode?
In this the register content is incremented or decremented after or before its value is used to access memory.
What is effective address?
Effective address is defined to be the memory address obtained from the computation dictated by the given addressing mode. This normally adds the address given in register or memory location with a constant to find the resultant address.
What is direct address mode?
The effective address is equal to the address part of the instruction. The operand resides in memory and its address is given directly by the address field of the instruction.
What is indirect address mode?
The address field of the instruction gives the address where effective address is stored in memory. Control fetched the instruction from memory and uses its address part to access memory again to read the effective address.
What is relative address mode?
In relative address mode, the content of the program counter is added to the address part of the instruction in order to obtain the effective address.
What is indexed addressing mode?
The content of the index register is added to the address part of the instruction to obtain the effective address.
What is base register addressing mode?
The content of the base register is added to the address part of the instruction to obtain the effective address.
What are the types of instructions?
i. Data transfer instructions
ii. Data manipulation instructions
iii. Program control instructions
What is data transfer instruction? List them.
Data transfer instructions move data from one place to another without changing the data content. They transfer data between memory and processor registers, between processor registers and input or output, and between processor register themselves.
They include
i) Load ii) Store iii) Move iv) Exchange
v) Input vi) Output vii) Push viii) Pop
What are data manipulation instructions? What are the types?
Data manipulation instructions perform operations on data and provide the computational capabilities for the computer. They are of three types:
i. Arithmetic instruction
ii. Logical and bit manipulation instructions
iii. Shift instructions
What are arithmetic instructions? List them.
The four basic arithmetic operation are: addition, subtraction, multiplication and division. They are Increment, Decrement, Add, Subtract, Multiply, Divide, Add with carry, Subtract with Borrow, Negate
What are the status register bits?
Carry, Sign, Zero, Overflow (Briefly explain them)
What is a program status word?
The collection of all status bit conditions in the CPU is called program status word or PSW.
What are the types of Interrupts?
There are three major types of interrupts that cause a break in the normal execution of a program. They can be classified as:
i. External Interrupts
ii. Internal Interrupts
iii. Software interrupts ¶ 1:44 AM
