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# CNTSR, Counter Status Register

The CNTSR characteristics are:

## Purpose

Provides counter frequency status information.

## Configuration

It is IMPLEMENTATION DEFINED whether CNTSR is implemented in the Core power domain or in the Debug power domain.

For more information, see 'Power and reset domains for the system level implementation of the Generic Timer'.

## Attributes

CNTSR is a 32-bit register.

## Field descriptions

31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0
RES0 | FCACK | RES0 | DBGH | RES0

#### Bits [31:18]

Reserved, RES0.

#### FCACK, bits [17:8]

Frequency Change Acknowledge. Indicates the currently selected entry in the Frequency modes table, see 'The Frequency modes table'.

The reset behavior of this field is:

- On a Timer reset, this field resets to 0.

#### Bits [7:2]

Reserved, RES0.

#### DBGH, bit [1]

Indicates whether the counter is halted because the Halt-on-debug signal is asserted:

DBGH | Meaning
--- | ---
0b0 | Counter is not halted.
0b1 | Counter is halted.

The reset behavior of this field is:

- On a Timer reset, this field resets to an architecturally UNKNOWN value.

#### Bit [0]

Reserved, RES0.

## Accessing CNTSR

In a system that supports the Realm Management Extension, the CNTControlBase frame, which includes this register, is implemented only in the Root physical address space.

In a system that supports Secure and Non-secure physical address spaces, the CNTControlBase frame, which includes this register, is implemented only in the Secure physical address space.

#### CNTSR can be accessed through the memory-mapped interfaces:

Component | Frame | Offset | Instance
--- | --- | --- | ---
Timer | CNTControlBase | 0x004 | CNTSR

Accesses on this interface are RO.

AArch32 Registers | AArch64 Registers | AArch32 Instructions | AArch64 Instructions | Index by Encoding | External Registers | External Registers by Offset | Registers by Functional Group | Proprietary Notice

26/03/2024 09:49; 67c0ae5282a7629ba0ea0ba7267b43cd4f7939f6

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