Difference between revisions of "Processor Status Word"
From Computer History Wiki
(An OK start) |
m (+cat) |
||
| (3 intermediate revisions by the same user not shown) | |||
| Line 1: | Line 1: | ||
| − | The '''Processor Status Word''' (often given as '''PS''' for short, or some variant) is a [[register]] in the [[Central Processing Unit|CPU]] which records important information about the state of the CPU. | + | The '''Processor Status Word''' or '''Program Status Word''' (often given as '''PS''' for short, or some variant) is a [[register]] in the [[Central Processing Unit|CPU]] which records important information about the state of the CPU. |
Information typically present in the PS includes: | Information typically present in the PS includes: | ||
* whether [[interrupt]]s are enabled; | * whether [[interrupt]]s are enabled; | ||
| − | * for [[time-sharing]] machines, whether the CPU is in 'User' or '[[Kernel]' mode; | + | * for [[time-sharing]] machines, whether the CPU is in 'User' or '[[Kernel]]' mode; |
* the [[condition codes]], for machines which keep them in the PS. | * the [[condition codes]], for machines which keep them in the PS. | ||
Some machines (e.g. the [[PDP-10]]) include the [[Program Counter]] in the PS. | Some machines (e.g. the [[PDP-10]]) include the [[Program Counter]] in the PS. | ||
| − | {{stub}} | + | {{semi-stub}} |
| + | |||
| + | [[Category:CPU Basics]] | ||
Latest revision as of 22:53, 14 December 2018
The Processor Status Word or Program Status Word (often given as PS for short, or some variant) is a register in the CPU which records important information about the state of the CPU.
Information typically present in the PS includes:
- whether interrupts are enabled;
- for time-sharing machines, whether the CPU is in 'User' or 'Kernel' mode;
- the condition codes, for machines which keep them in the PS.
Some machines (e.g. the PDP-10) include the Program Counter in the PS.
