Which are the flags of status register?
Common flags
| Flag | Name |
|---|---|
| Z | Zero flag |
| C | Carry flag |
| S / N | Sign flag Negative flag |
| V / O / W | Overflow flag |
Which of the following flag is not present in 8085?
Zero flag is present in 8085 but not in the 8051.
How many types of flag registers are there?
There are total 9 flags in 8086 and the flag register is divided into two types: (a) Status Flags – There are 6 flag registers in 8086 microprocessor which become set(1) or reset(0) depending upon condition after either 8-bit or 16-bit operation. These flags are conditional/status flags.
What is the function of auxiliary carry flag?
The Auxiliary flag is set (to 1) if during an “add” operation there is a carry from the low nibble (lowest four bits) to the high nibble (upper four bits), or a borrow from the high nibble to the low nibble, in the low-order 8-bit portion, during a subtraction.
What is the function of carry flag?
In computer processors the carry flag (usually indicated as the C flag) is a single bit in a system status register/flag register used to indicate when an arithmetic carry or borrow has been generated out of the most significant arithmetic logic unit (ALU) bit position.
What is carry flag with example?
Carry Flag is a flag set when: a) two unsigned numbers were added and the result is larger than “capacity” of register where it is saved. Ex: we wanna add two 8 bit numbers and save result in 8 bit register. In your example: 255 + 9 = 264 which is more that 8 bit register can store.
What is difference between carry flag and overflow flag?
Carry Flag is a flag set when: a) two unsigned numbers were added and the result is larger than “capacity” of register where it is saved. Overflow Flag is used as CF but when we work on signed numbers. Ex we wanna add two 8 bit signed numbers: 127 + 2.
How do you clear a flag?
1 Answer. The best way to clear the carry flag is to use the CLC instruction; and the best way to set the carry flag is to use the STC instruction.
What is clear carry flag?
Notes: CLC simply sets the Carry flag (CF) to the cleared (0) state. Use CLC in situations where the Carry flag must be in a known cleared state before work begins, as when you are rotating a series of words or bytes using the rotate instructions RCL and RCR.
How do you set a carrying flag?
The carry flag is set if the addition of two numbers causes a carry out of the most significant (leftmost) bits added. 2. The carry (borrow) flag is also set if the subtraction of two numbers requires a borrow into the most significant (leftmost) bits subtracted.
Which flag is set when result is positive or negative?
Sign Flag (SF) – set to 1 when result is negative. When result is positive it is set to 0. Actually this flag take the value of the most significant bit. Overflow Flag (OF) – set to 1 when there is a signed overflow.