Introduction 
It often contains a pointer to the next one needs to be executed. The program status word also typically contains an error status area and a conditional code for interrupts allow or disabled, super or normal user mode bit.
In a computer system, it indicates that the component of the system is operating is program status word
program status word PSW (Program Status Word) included the status bit carry flag (CF) , is zero sign bit (ZF) , symbol flag (sf) , overflow flag (Of) , Trap marker (TF) , Interrupt Enable (Interrupt Shield) Sign (IF) , Virtual Interrupt Sign ( VIF) , Virtual Interrupt Symbol (VIP) , i0 privilege level (IOPL) .
Usually Status Code: The working status code of the CPU - indicates that the native is still genk, used to explain the operating system or a general user on the CPU, thereby determining whether it can use privileges Or have other special powers. Condition code - reflect the result feature after the instruction execution. Interrupt shielding code - indicates whether it is allowed to be interrupted.
The conversion between the individual states: the only way to control the conversion of the tube is through interruption. Human-natively available settings PSW (modified program status word) can achieve