The CNTSCR characteristics are:
Enables the counter, controls the counter frequency setting, and controls counter behavior during debug.
It is IMPLEMENTATION DEFINED whether CNTSCR is implemented in the Core power domain or in the Debug power domain.
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'.
CNTSCR is a 32-bit register.
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 |
ScaleVal |
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:
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.
Component | Frame | Offset | Instance |
---|---|---|---|
Timer | CNTControlBase | 0x10 | CNTSCR |
Accesses on this interface are RW.
04/07/2023 11:22; 1b994cb0b8c6d1ae5a9a15edbc8bd6ce3b5c7d68
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