Concept
Mode protégé
Concepts associés (26)
PC Magazine
PC Magazine (shortened as PCMag) is an American computer magazine published by Ziff Davis. A print edition was published from 1982 to January 2009. Publication of online editions started in late 1994 and continued . PC Magazine provides reviews and previews of the latest hardware and software for the information technology professional. Articles are written by leading experts including John C. Dvorak, whose regular column and "Inside Track" feature were among the magazine's most popular attractions.
Double fault
On the x86 architecture, a double fault exception occurs if the processor encounters a problem while trying to service a pending interrupt or exception. An example situation when a double fault would occur is when an interrupt is triggered but the segment in which the interrupt handler resides is invalid. If the processor encounters a problem when calling the double fault handler, a triple fault is generated and the processor shuts down.
Multiuser DOS
Multiuser DOS is a real-time multi-user multi-tasking operating system for IBM PC-compatible microcomputers. An evolution of the older Concurrent CP/M-86, Concurrent DOS and Concurrent DOS 386 operating systems, it was originally developed by Digital Research and acquired and further developed by Novell in 1991. Its ancestry lies in the earlier Digital Research 8-bit operating systems CP/M and MP/M, and the 16-bit single-tasking CP/M-86 which evolved from CP/M.
Segment d'état de tâche
Un segment d'état de tâche ou Task state segment (TSS) est une structure spécifique aux processeurs de la famille x86 où est stockée tout le contexte d'un processus. Son descripteur est placé dans la GDT (Table globale de descripteurs). En tant que segment, les segments d'état de tâche sont référencés par des descripteurs d'état de tâche (TSSD) situés dans la GDT.
DESQview
DESQview (DV) is a text mode multitasking operating environment developed by Quarterdeck Office Systems which enjoyed modest popularity in the late 1980s and early 1990s. Running on top of DOS, it allows users to run multiple programs concurrently in multiple windows. Quarterdeck's predecessor to DESQview was a task switching product called Desq (shipped late April or May 1984), which allows users to switch between running programs. Quarterdeck revamped its package, bringing multitasking in, and adding TopView compatibility.
Mémoire étendue
La mémoire étendue se rapporte aux adresses de mémoire vive au-delà du premier mégaoctet pour les compatibles PCs équipés d'un processeur 80286 ou postérieur. Cette mémoire n'est accessible qu'en basculant le processeur x86 en mode protégé (sinon le processeur n'est capable d'accéder qu'à d'adresses mémoire). C'est par exemple le cas lorsque le driver EMM386.EXE a été chargé. À cause d'un bug d'implémentation, en mode 8086 virtuel le processeur est quand même capable d'accéder aux premiers de la mémoire étendue, ce bug a été largement exploité pour accéder à une zone qui a été nommée HMA (abréviation de high memory area en anglais).