17.5.5 Debugger Security

The DSU provides Debug Access Level (DAL) mechanism which disable or limit the debugger access into the device. The DAL settings are programed through the ROMCFG.DAL fuse configuration bits.

The DSU DAL feature provides three levels of access. The following table describes the debugger access levels:

Table 17-1. Debugger Access Level Through DAP
DAL Setting	DSU Address Space		System Memory Regions ⁽¹⁾		Hot Plugging	Cold Plugging
DAL Setting	External	Internal	Secure	Non-Secure	Hot Plugging	Cold Plugging
DAL 0	X	-	-	-	-	X
DAL 1⁽¹⁾	X	-	-	X	X	X
DAL 2	X	X	X	X	X	X
Note: Only available on PIC32CM SG devices. Secure requests are converted to non-secure request in the CPU.

If the debugger attempts to access a device region which is not permitted by the current DAL setting, a bus error is returned to the CoreSight AP hardware which results in the assertion of the ARM DP sticky error bit.

In DAL0 mode, debugger breakpoints are disabled.