DocID018909 Rev 11 1685/1731
RM0090 Debug support (DBG)
1701
38.10 Core debug
Core debug is accessed through the core debug registers. Debug access to these registers
is by means of the Advanced High-performance Bus (AHB-AP) port. The processor can
access these registers directly over the internal Private Peripheral Bus (PPB).
It consists of 4 registers:
Note: Important: these registers are not reset by a system reset. They are only reset by a power-
on reset.
Refer to the Cortex
®
-M4 with FPU r0p1 TRM for further details.
To Halt on reset, it is necessary to:
• enable the bit0 (VC_CORRESET) of the Debug and Exception Monitor Control
Register
• enable the bit0 (C_DEBUGEN) of the Debug Halting Control and Status Register.
Table 302. Core debug registers
Register Description
DHCSR
The 32-bit Debug Halting Control and Status Register
This provides status information about the state of the processor enable core debug
halt and step the processor
DCRSR
The 17-bit Debug Core Register Selector Register:
This selects the processor register to transfer data to or from.
DCRDR
The 32-bit Debug Core Register Data Register:
This holds data for reading and writing registers to and from the processor selected
by the DCRSR (Selector) register.
DEMCR
The 32-bit Debug Exception and Monitor Control Register:
This provides Vector Catching and Debug Monitor Control. This register contains a
bit named TRCENA which enable the use of a TRACE.