What is the status register?

Status Register - also known as Flag Register, Status Word of Program and Code register - is defined as a team of flag bits inside the processor. The register is a processor circuit and is like memory location, which means that the data can be written and read from it. Unlike the location of the memory, the register often does not address the address because the microprocessor uses it internally. In the central processing unit (CPU), which is 8 -bit, the status registry bit may be equal to number 1 or cleaned , equal to the number 0, according to the results of the processor operation. The processor sometimes sets or cleans the bits themselves, but at other times the specific instructions of the program set or clean bits. Each flag in the status register has a unique purpose. The transmission symptom sets up if the previous operation has performed the seventh bit & mpomlčka; or negative flag - overflow or make a bribe of flag. It is located during logic shifts, comparison and arithmetic. Zero symptoms of a set if the last result of the operacE was 0.

The symptom called "Interrupt Discrupt Discrupte" works by enabling or disabling the operation of the interruption, which are instructions that temporarily stop certain operations in order to perform other operations. If this particular symptom is set, they must not operate an interruption, but if it is clear, interruptions are allowed. Another symptom called Decimal Signs allows the processor to monitor the more advanced binary regime for performing flawless arithmetic equations. When the symptom sets, it uses this advanced binary regime. Another battle of the registry is Bit Break Bit, which sets up when the power interrupt command is made.

6 The result of the lid. The negative symptom sets up if the latest operation result was set to 1. The last symptom called Bit 5 is nameless and always set to 1. Programmers basically do not have this particular bit.

Symptoms register is one of the potentialsThe importance of the status register, which was used in some central processor units and contained the current processor states. It was 16 bits wide and followed by Eflags and Rflags, a 32 -bit register and a 64 -bit register. The flag register, however, had some flags that differed from the original 8 -bit register, including a symptom of parity, auxiliary flag and a trap flag.