3.15.40. Lock Status Register

The LSR characteristics are:

Purpose

Indicates the status of the lock control mechanism. This lock prevents accidental writes. When locked, write accesses are denied for all registers except for the LAR. The lock registers do not affect accesses from the external debug interface. This register reads as 0 when accessed from the external debug interface.

Usage constraints

There are no usage constraints.

Configurations

This register is available in all configurations.

Attributes

See the register summary in Table 3.151.

Figure 3.182 shows the bit assignments.

Figure 3.182. LSR bit assignments

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Table 3.191 shows the bit assignments.

Table 3.191. LSR bit assignments

BitsNameFunction
[31:3]Reserved

-

[2]nTT

Register size indicator. Always 0. Indicates that the LAR is implemented as 32-bit.

[1]SLK

Software Lock Status. Returns the present lock status of the device, from the current interface.

0

Indicates that write operations are permitted from this interface.

1

Indicates that write operations are not permitted from this interface. Read operations are permitted.

[0]SLI

Software Lock Implemented. Indicates that a lock control mechanism is present from this interface.

0

Indicates that a lock control mechanism is not present from this interface. Write operations to the LAR are ignored.

1

Indicates that a lock control mechanism is present from this interface.


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