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UM10360_0
© NXP B.V. 2009. All rights reserved.
User manual
Rev. 00.06 — 5 June 2009
755 of 808
NXP Semiconductors
UM10360
Chapter 34: Appendix: Cortex-M3 User Guide
If a different frequency is used than that intended by the factory preset value, calculate the
calibration value required from the frequency of the processor clock or external clock.
4.4.5 SysTick design hints and tips
The SysTick counter runs on the processor clock. If this clock signal is stopped for low
power mode while the SysTick counter is running from it, the SysTick counter will stop.
Ensure software uses aligned word accesses to access the SysTick registers.
[30]
SKEW
Indicates whether the value of TENMS is precise. This can affect the
suitability of SysTick as a software real time clock. This value is factory
preset as described in
.
[29:24]
-
Reserved.
[23:0]
TENMS
This value is factory preset as described in
Table 650. CALIB register bit assignments
Bits
Name
Function