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# CNTSR, Counter Status Register

The CNTSR characteristics are:

## Purpose

Provides counter frequency status information.

## Configuration

The power domain of CNTSR is IMPLEMENTATION DEFINED.

Some or all fields in this register have defined reset values. These apply only on a reset of the reset domain in which the register is implemented. The register is not affected by a reset of any other reset domain. For more information see 'Power and reset domains for the system level implementation of the Generic Timer' in Chapter I1 of the Arm® Architecture Reference Manual, Armv8, for Armv8-A architecture profile.

## Attributes

CNTSR is a 32-bit register.

## Field descriptions

The CNTSR bit assignments are:

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
FCACK | RES0 | DBGH | RES0

#### FCACK, bits [31:8]

Frequency change acknowledge. Indicates the currently selected entry in the Frequency modes table, see 'The Frequency modes table' in Chapter I1 of the Arm® Architecture Reference Manual, Armv8, for Armv8-A architecture profile.

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.

This field resets to an architecturally UNKNOWN value.

#### Bit [0]

Reserved, RES0.

## Accessing the CNTSR

In a system that supports Secure and Non-secure memory maps the CNTControlBase frame, that includes this register, is implemented only in the Secure memory map.

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

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

Access on this interface is RO.

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

15/04/2019 16:47; 8c23526ba8a13a72aada4137daf3e3977b49036e

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