Datasheet

228
SAM4S Series [DATASHEET]
11100F–ATARM–29-Jan-14
12.10.1.2 SysTick Reload Value Registers
Name: SYST_RVR
Access: Read/Write
Reset: 0x000000000
The SYST_RVR specifies the start value to load into the SYST_CVR.
• RELOAD: SYST_CVR Load Value
Value to load into the SYST_CVR when the counter is enabled and when it reaches 0.
The RELOAD value can be any value in the range 0x00000001–0x00FFFFFF. A start value of 0 is possible, but has no effect
because the SysTick exception request and COUNTFLAG are activated when counting from 1 to 0.
The RELOAD value is calculated according to its use: For example, to generate a multi-shot timer with a period of N processor
clock cycles, use a RELOAD value of N-1. If the SysTick interrupt is required every 100 clock pulses, set RELOAD to 99.
31 30 29 28 27 26 25 24
–
23 22 21 20 19 18 17 16
RELOAD
15 14 13 12 11 10 9 8
RELOAD
76543210
RELOAD