Clear Task-Switched (clts)

clts

Operation

0 -> TS Flag in CR0

Description

The task-switched flag in register CR0 is cleared by clta. The TS Flag is set by the 80386 for each task switch. The TS Flag is used as follows:

• If the TS Flag is set, each execution of the ESC instruction is trapped.

• If the TS Flag and the MP Flag are both set, execution of a Wait instruction is trapped.

If a task switch is made after an ESC instruction is started, save the processor extension context before a new ESC instruction can be run. The fault handler resets the TS Flag and saves the context.

clts is not used in application program, it is used in operating systems.

clts can only be executed at privilege level 0.

Example

Clear the TS flag:

clts