Atmel SAM4S Xplained Pro Starter Kit Atmel ATSAM4S-XSTK ATSAM4S-XSTK Data Sheet

 173

SAM4S [DATASHEET]

11100E–ATARM–24-Jul-13

Supervisor Call.

Syntax

SVC{cond} #imm

where:

cond

imm

is an expression evaluating to an integer in the range 0-255 (8-bit value).

Operation

The SVC instruction causes the SVC exception.

imm is ignored by the processor. If required, it can be retrieved by the exception handler to determine what service is
being requested.

Condition Flags

This instruction does not change the flags.

Examples

SVC  0x32  ; Supervisor Call (SVC handler can extract the immediate value

           ; by locating it via the stacked PC) 

Wait for Interrupt.

Syntax

WFI{cond}

where:

cond

Operation

WFI is a hint instruction that suspends execution until one of the following events occurs:



An exception



A Debug Entry request, regardless of whether Debug is enabled.

Condition Flags

This instruction does not change the flags.

Examples

WFI ; Wait for interrupt