2.6.10.1.2 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.