The contents of register or memory and carry flag cy are added to the contents of. Flag register in 8085 microprocessor geeksforgeeks. And based upon the value of result after any type of arithmetic and logical operation the value of flag bits become either set 1 or. What type of architecture used in 8085 microprocessor. Flag register of 8085 microprocessor with example 8085. Microprocessor multiple choice questions and answersintel. The different flags and their positions in flag register are shown in following fig. In most of the operations, the result is stored in the accumulator. Intel 8085 8bit microprocessor shrimati indira gandhi. The flags register is the status register in intel x86 microprocessors that contains the current. Depending upon the value of result after any arithmetic and logical operation the flag bits become set 1 or reset. An instruction is a binary pattern designed inside a microprocessor. Flag register of 8086 microprocessor geeksforgeeks. Sf sign flag zf zero flag ac auxiliary carry flag pf parity flag cf carry flag.
Lecture note on microprocessor and microcontroller theory. These five flags are of 1bit ff and are known as zero, sign, carry, parity and auxiliary. The flags register it is a 16bit register, also called. These five flags are of 1bit ff and are known as zero, sign, carry, parity and auxiliary carry. There are five flags present in 8085 microprocessor. There are following flag bits used into the flag registers. Here this video is a part of microprocessor and interfacing 8085. The flag register is a special purpose register and is completely different from the other registers in a microprocessor.
Explain briefly the flag register in the 8085 microprocessor. This flag is set whenever there has been a carry out of, or a borrow into, the higher order bit of the result. In 8085 microprocessor, the flags register can have a total of eight flags. Prerequisite flag register in 8085 microprocessor the flag register is a special purpose register. Flags register in 8085 microprocessor tutorialspoint. The 8085 has 8 bit flag register specifying the status of the result generated in accumulator.
Here, we are going learn about the different types of flag registers of 8085 microprocessor. Flag register in the 8085 microprocessor career ride. Explain flag register of 8085 microprocessor ques10. In 8085 microprocessor, flag register consists of 8 bits and only 5 of them are useful. The flag is used by the instructions that add amd subtract multibyte numbers.
It indicates some condition produced by the execution of an instruction. Thus a flag can be represented by 1 bit of information. The respective position of these flag bits in flag register has been show the below figure. Flag register of 8085 microprocessor with example 8085 auxiliary. In 8085 microprocessor, how many interrupts are maskable. The flag register contain status bits that indicates various status about the result generated. Interview questions on microprocessor with detailed answers. In this video, i have explained flag register of 8085 by following outlines. The adjust flag used to be called auxiliary carry bit in 8080 and halfcarry bit in the zilog z80 architecture. Flags are flipflops that store bit 0 or 1 based on the arithmetic or logical operation performed by an arithmetic and logical unit alu. Flag register of 8085 microprocessor is explained using proper example.
Prerequisite registers of 8085 microprocessor the flag register is a special purpose register. Status or flag register in 8085 microprocessor electricalvoice. The flag register in 8085 is an 8bit register which contains 5 bit positions. The flag register is basically a special type of register or we can also say that they are special purpose register. Figure format of flag register there are total 9 flags in 8086 and the flag register is divided into two types. Depending upon the value of result after any arithmetic and logical operation the flag bits become set 1 or reset 0. This allows instructions following to act accordingly, such as a branch as a result of two values comparing equal. Registers used in 8085 microprocessor student study hub.1210 317 1160 1055 1182 205 786 1262 663 1514 281 980 1280 839 376 1169 549 1184 864 930 272 750 1222 837 366 35 244 1133 977 369 1496 706 429