# Program Status Word

> control register in IBM System/360 and successors systems architecture

**Wikidata**: [Q9063099](https://www.wikidata.org/wiki/Q9063099)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Program_status_word)  
**Source**: https://4ort.xyz/entity/program-status-word

## Summary
The Program Status Word (PSW) is a control register in IBM System/360 and successor systems architecture, functioning as a status register that provides additional information about a processor's result. It is a key component in the IBM mainframe architecture, influencing system behavior and error handling.

## Key Facts
- A type of status register used in IBM System/360 and related systems
- Contains flags providing supplementary information about a processor's operation
- Part of the IBM mainframe architecture, introduced in the System/360 series
- Aliases include "程序状态字" in Chinese
- Linked to the concept of a status register in computer architecture
- Sitelinks available in multiple languages, including English, Spanish, and Chinese
- Wikidata description confirms its role as a control register in IBM systems

## FAQs
### Q: What is the Program Status Word used for?
A: The Program Status Word is a control register that stores flags and additional information about a processor's result, influencing system behavior and error handling in IBM mainframe systems.

### Q: Which IBM systems use the Program Status Word?
A: The Program Status Word is used in IBM System/360 and successor systems, including later mainframe architectures.

### Q: How does the Program Status Word differ from other status registers?
A: While similar to other status registers, the Program Status Word is specifically designed for IBM mainframe systems, particularly the System/360 series and its successors.

### Q: Is the Program Status Word still relevant today?
A: Yes, the Program Status Word remains a foundational concept in IBM mainframe architecture, though modern systems may implement variations or enhancements.

### Q: What languages are available for Program Status Word documentation?
A: Documentation is available in multiple languages, including Catalan, English, Spanish, Persian, Dutch, Norwegian, Ukrainian, and Chinese.

## Why It Matters
The Program Status Word is a critical component of IBM mainframe architecture, particularly in the System/360 series and its successors. It plays a pivotal role in system control and error handling by providing additional status information to the processor. This register ensures efficient operation and reliable performance in IBM mainframe environments. Its design reflects IBM's commitment to robust and scalable computing solutions, influencing how mainframe systems manage and respond to computational tasks. The Program Status Word remains a key reference in understanding the inner workings of IBM's legacy and modern mainframe architectures.

## Notable For
- Being a foundational control register in IBM System/360 and successor systems
- Providing supplementary status information to enhance processor functionality
- Supporting error handling and system control in mainframe environments
- Available in multiple languages, indicating its widespread relevance
- Linked to the broader concept of status registers in computer architecture

## Body
### Definition and Role
The Program Status Word (PSW) is a control register in IBM mainframe systems, particularly the System/360 series and its successors. It functions as a status register, storing flags and additional information about a processor's result. This information is crucial for system behavior and error handling.

### Architectural Significance
The PSW is part of IBM's mainframe architecture, introduced in the System/360 series. It plays a key role in system control, ensuring efficient operation and reliable performance. The register's design reflects IBM's focus on robust and scalable computing solutions.

### Language Support
Documentation for the Program Status Word is available in multiple languages, including Catalan, English, Spanish, Persian, Dutch, Norwegian, Ukrainian, and Chinese. This multilingual support highlights its global relevance and widespread use.

### Related Concepts
The Program Status Word is linked to the broader concept of status registers in computer architecture. It shares similarities with other status registers but is specifically tailored for IBM mainframe systems. This specialization makes it a unique and essential component in IBM's computing ecosystem.

### Historical Context
The Program Status Word was introduced alongside the System/360 series, a landmark in IBM's mainframe history. It remains a critical reference in understanding the architecture of IBM mainframe systems, both in their original form and in modern implementations.