12.5.3. Lock Access Register

The DBGLAR is a write-only register that controls writes to the debug registers. The purpose of the DBGLAR is to reduce the risk of accidental corruption to the contents of the debug registers. It does not prevent all accidental or malicious damage. Because the state of the DBGLAR is in the debug power domain, it is not lost when the processor powers down.

DBGLAR [31:0] contain a key that controls the lock status. To unlock the debug registers, write a 0xC5ACCE55 key to this register. To lock the debug registers, write any other value. Accesses to locked debug registers are ignored. The lock is set on reset.

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