Debug support (DBG) RM0367
956/1043 RM0367 Rev 7
33 Debug support (DBG)
33.1 Overview
The STM32L0x3 devices are built around a Cortex
®
-M0+ core which contains hardware
extensions for advanced debugging features. The debug extensions allow the core to be
stopped either on a given instruction fetch (breakpoint) or data access (watchpoint). When
stopped, the core’s internal state and the system’s external state may be examined. Once
examination is complete, the core and the system may be restored and program execution
resumed.
The debug features are used by the debugger host when connecting to and debugging the
STM32L0x3 MCUs.
One interface for debug is available:
• Serial wire
Figure 315. Block diagram of STM32L0x3 MCU and Cortex
®
-M0+-level debug support
1. The debug features embedded in the Cortex
®
-M0+ core are a subset of the Arm
®
CoreSight Design Kit.
The Arm
®
Cortex
®
-M0+ core provides integrated on-chip debug support. It is comprised of:
• SW-DP: Serial wire
• BPU: Break point unit
• DWT: Data watchpoint trigger
Cortex-M0
Core
SW-DP
Bridge
NVIC
DWT
BPU
System
interface
Debug AP
Bus matrix
DBGMCU
STM32 MCU debug suppo rt
Cortex-M0 debug support
SWDIO
SWCLK
MS19240V2
Debug AP