What is the difference between conditional and control flags in 8086 microprocessor?

Answer 1

Control Flag Register:

The Control Flag Register (CFR), also known as the Program Status Word (PSW), is a register used to control the execution flow and behavior of the processor. It typically stores various control flags that govern different aspects of the CPU's operation. Some common flags found in the Control Flag Register include:

Carry Flag (CF): Used to indicate whether an arithmetic operation generated a carry or borrow.

Zero Flag (ZF): Indicates whether the result of an operation is zero.

Sign Flag (SF): Indicates the sign (positive or negative) of the result.

Overflow Flag (OF): Indicates whether an arithmetic operation resulted in an overflow.

Interrupt Flag (IF): Determines whether interrupts are enabled or disabled.

The Control Flag Register provides control over program execution, including branching, interrupt handling, and arithmetic operations. It helps determine the outcome of operations and can be used for conditional branching based on specific flag states.

Conditional Flag Register:

The Conditional Flag Register (CFR), also known as the Condition Code Register (CCR) or Status Register (SR), contains flags that reflect the result of the most recent arithmetic or logical operation performed by the processor. These flags are used to perform conditional branching and control the flow of instructions based on specific conditions.

The flags present in the Conditional Flag Register can vary depending on the processor architecture, but some common flags include:

Zero Flag (ZF): Indicates whether the result of an operation is zero.

Sign Flag (SF): Indicates the sign (positive or negative) of the result.

Overflow Flag (OF): Indicates whether an arithmetic operation resulted in an overflow.

Carry Flag (CF): Used to indicate whether an arithmetic operation generated a carry or borrow.

Auxiliary Carry Flag (AF): Indicates a carry or borrow from the lower-order nibble (4 bits) to the higher-order nibble.

The Conditional Flag Register is primarily used for conditional jumps or branches, allowing the processor to alter the program flow based on the current flag states.

To summarize, the Control Flag Register focuses on controlling the processor's behavior and handling interrupts, while the Conditional Flag Register reflects the outcome of arithmetic and logical operations and enables conditional branching based on flag states.

Answer 2

control flags will be set or reset only by the processor. and conditional flags will be controlled(set /reset) by the programmer.