Chapter 26 Flashcards
What CLI do
CLI clears the interrupt flag to disable the interrupt system completely.
Why we stop all interruptions while changing a real time interrupt vector
So the system do not crash
What is Interrupt Chaining
We can transfer control to the original BIOS ISR in the end of our routine.
What is TSR
Terminate and Stay Resident
What is transient program area
Programs are loaded and executed in this area and the space reclaimed on their exit.
What is freemem pointer
Freemem pointer points where the free memory begins in DOS.
Who is responsible for Freemem pointer actions
DOS service 4C
What is service 31
This service is for legally terminate a program and give control back to DOS
What happen when interrupt routine was overwritten
Program crashes
What is DOSKEY
An extension to the operation system
Is DOSKEY TSR
Yes
What mem/c command do
This command displays all currently loaded drivers and the current state of memory. Our program also become a part of DOS.
