CNTSCR, Counter Scale Register

The CNTSCR characteristics are:

Purpose

Enables the counter, controls the counter frequency setting, and controls counter behavior during debug.

Configuration

The power domain of CNTSCR is IMPLEMENTATION DEFINED.

This register is present only when FEAT_CNTSC is implemented. Otherwise, direct accesses to CNTSCR are RES0.

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

Attributes

CNTSCR is a 32-bit register.

Field descriptions

313029282726252423222120191817161514131211109876543210
ScaleVal

ScaleVal, bits [31:0]

Scale Value

When counter scaling is enabled, ScaleVal is the average amount added to the counter value for one period of the frequency of the Generic counter as described in the CNTFRQ register.

The actual rate of update of the counter value is determined by the counter update frequency.

ScaleVal is expressed as an unsigned fixed point number with an 8-bit integer value and a 24-bit fractional value.

CNTSCR.ScaleVal can only be changed when CNTCR.EN == 0. If the value of this field is changed when CNTCR.EN == 1:

The reset behavior of this field is:

Accessing CNTSCR

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.

CNTSCR can be accessed through the memory-mapped interfaces:

ComponentFrameOffsetInstance
TimerCNTControlBase0x10CNTSCR

Accesses to this interface are RW.


30/09/2022 15:57; 21c5a6dd0fdaf10a712e2f2d6fffbdbd66d4d96f

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