3.5.61. Lock Access Register, ETMLAR, ETMv3.2 and later

The ETMLAR characteristics are:


Locks and unlocks access to all other ETM registers.

Usage constraints

Writes to this register from an interface that ignores the lock registers are ignored.

In ETMv3.5 coprocessor accesses to ETMLAR are unpredictable.


This register is only available in ETMv3.2 or later.


See the register summary in Table 3.3 and Reset behavior.

Figure 3.54 shows the ETMLAR bit assignments.

Figure 3.54. ETMLAR bit assignments

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Table 3.69 shows the ETMLAR bit assignments.

Table 3.69. ETMLAR bit assignments


Version [a]




Write 0xC5ACCE55 to this field to unlock the ETM.

Write any other value to this field to lock the ETM.

[a] The first ETM architecture version that defines the field.

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