How do you set a parity flag?

How do you set a parity flag?

For example, assume a machine where a set parity flag indicates even parity. If the result of the last operation were 26 (11010 in binary), the parity flag would be 0 since the number of set bits is odd. Similarly, if the result were 10 (1010 in binary) then the parity flag would be 1.

What is the use of flag register?

The Flag register is a Special Purpose Register. Depending upon the value of result after any arithmetic and logical operation the flag bits become set (1) or reset (0). In 8085 microprocessor, flag register consists of 8 bits and only 5 of them are useful.

Which register is referred as flag register?

The FLAGS register is the status register that contains the current state of the CPU. The adjust flag used to be called auxiliary carry bit in 8080 and half-carry bit in the Zilog Z80 architecture. In i386 architecture the register is 16 bits wide.

Which flag resets when the result is odd or even?

if the number is even it will set the zero flag to 1, and if it is odd it resets the flag to 0.

Why do we use parity flag?

Some CPUs (notably x86 CPUs) feature a parity flag on their status register. This flag indicates whether the number of bits of the result of an operation is odd or even.

What is the purpose of Zero flag?

Along with a carry flag, a sign flag and an overflow flag, the zero flag is used to check the result of an arithmetic operation, including bitwise logical instructions. It is set to 1, or true, if an arithmetic result is zero, and reset otherwise.

What is difference between carry and auxiliary carry flag?

The auxiliary carry flag AF watches for a 4-bit (nibble) carry, while the common carry flag CF watches for a carry-out from the MSB of the operand size.

Which are different flags in PSW register?

The program status word (PSW) register is an 8-bit register, also known as flag register. It is of 8-bit wide but only 6-bit of it is used….8051 Flag Bits and PSW Register.

CY PSW.7 Carry Flag
RS0 PSW.3 Register Bank selector bit 0
OV PSW.2 Overflow Flag
PSW.1 User definable FLAG

Is accumulator a special purpose register?

Special Purpose Registers. An accumulator is a register for short-term, intermediate storage of arithmetic and logic data in a computer’s CPU (Central Processing Unit). In an arithmetic operation involving two operands, one operand has to be in this register.

Which instruction does not affect any flag?

As there is no arithmetic or logical operation being performed, no flags are affected by data transfer instructions. Arithmetic instruction: Arithmetic Instructions are the instructions that perform basic arithmetic operations such as addition, subtraction, and a few more.

What is the mean of parity?

1 : the quality or state of being equal or equivalent Women have fought for parity with men in the workplace. 2a : equivalence of a commodity price expressed in one currency to its price expressed in another The two currencies are approaching parity for the first time in decades.

What does parity bit do?

A parity bit, or check bit, is a bit added to a string of binary code. Parity bits are a simple form of error detecting code. The parity bit ensures that the total number of 1-bits in the string is even or odd. Accordingly, there are two variants of parity bits: even parity bit and odd parity bit.