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GD32F403xx User Manual
372
16.4.4.
Function overview
Clock source configuration
The general level2 TIMER can only being clocked by the CK_TIMER.
◼
Internal timer clock CK_TIMER which is from module RCU
The general level2 TIMER has only one clock source which is the internal CK_TIMER, used
to drive the counter prescaler. When the CEN is set, the CK_TIMER will be divided by PSC
value to generate PSC_CLK.
The TIMER_CK, driven counter’s prescaler to count, is equal to CK_TIMER which is from
RCU
Figure 16-59. Timing chart of internal clock divided by 1
CK_TIMER
CEN
PSC_CLK = TIMER_CK
CNT_REG
Reload Pulse
17
18
19
20
21
22
update event
generate(UPG)
23
00
01
02
03
04
05
06
07
Update event (UPE)
Clock prescaler
The counter clock (PSC_CK) is obtained by the TIMER_CK through the prescaler, and the
prescale f actor can be configured f rom 1 to 65536 through the prescaler register
(TIMERx_PSC). The new written prescaler value will not take effect until the next update
event.