Atmel SAM4S-XPLD Atmel ATSAM4S-XPLD ATSAM4S-XPLD Hoja De Datos

 169

SAM4S [DATASHEET]

11100E–ATARM–24-Jul-13

Breakpoint.

Syntax

BKPT #imm

where:

imm

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

Operation

The BKPT instruction causes the processor to enter Debug state. Debug tools can use this to investigate system state
when the instruction at a particular address is reached.

imm is ignored by the processor. If required, a debugger can use it to store additional information about the breakpoint.

The BKPT instruction can be placed inside an IT block, but it executes unconditionally, unaffected by the condition
specified by the IT instruction.

Condition Flags

This instruction does not change the flags.

Examples

BKPT 0xAB

; Breakpoint with immediate value set to 0xAB (debugger can

; extract the immediate value by locating it using the PC)

Note:

ARM does not recommend the use of the BKPT instruction with an immediate value set to 0xAB for any purpose 
other than Semi-hosting.

Change Processor State. 

Syntax

CPSeffect iflags

where:

effect

is one of:

IE 

Clears the special purpose register.

ID 

Sets the special purpose register.

iflags

is a sequence of one or more flags:

i 

Set or clear PRIMASK.

f 

Set or clear FAULTMASK. 

Operation

CPS changes the PRIMASK and FAULTMASK special register values. See 

 

for more

information about these registers.

Restrictions

The restrictions are:



Use CPS only from privileged software, it has no effect if used in unprivileged software



CPS cannot be conditional and so must not be used inside an IT block.

Condition Flags

This instruction does not change the condition flags.