
RM0453 Rev 2
929/1454
RM0453
General-purpose timers (TIM16/TIM17)
944
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
OC1M
[3]
rw
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
OC1M[2:0]
OC1PE OC1FE
CC1S[1:0]
rw
rw
rw
rw
rw
rw
rw
Bits 31:17 Reserved, must be kept at reset value.
Bits 15:7 Reserved, must be kept at reset value.
Bits 16, 6:4
OC1M[3:0]
: Output Compare 1 mode
These bits define the behavior of the output reference signal OC1REF from which OC1 and
OC1N are derived. OC1REF is active high whereas OC1 and OC1N active level depends
on CC1P and CC1NP bits.
0000: Frozen - The comparison between the output compare register TIMx_CCR1 and the
counter TIMx_CNT has no effect on the outputs.
0001: Set channel 1 to active level on match. OC1REF signal is forced high when the
counter TIMx_CNT matches the capture/compare register 1 (TIMx_CCR1).
0010: Set channel 1 to inactive level on match. OC1REF signal is forced low when the
counter TIMx_CNT matches the capture/compare register 1 (TIMx_CCR1).
0011: Toggle - OC1REF toggles when TIMx_CNT=TIMx_CCR1.
0100: Force inactive level - OC1REF is forced low.
0101: Force active level - OC1REF is forced high.
0110: PWM mode 1 - Channel 1 is active as long as TIMx_CNT<TIMx_CCR1 else inactive.
0111: PWM mode 2 - Channel 1 is inactive as long as TIMx_CNT<TIMx_CCR1 else active.
All other values: Reserved
Note: These bits can not be modified as long as LOCK level 3 has been programmed (LOCK
bits in TIMx_BDTR register) and CC1S=’00’ (the channel is configured in output).
In PWM mode 1 or 2, the OCREF level changes only when the result of the
comparison changes or when the output compare mode switches from “frozen” mode
to “PWM” mode.
The OC1M[3] bit is not contiguous, located in bit 16.
Bit 3
OC1PE
: Output Compare 1 preload enable
0: Preload register on TIMx_CCR1 disabled. TIMx_CCR1 can be written at anytime, the
new value is taken in account immediately.
1: Preload register on TIMx_CCR1 enabled. Read/Write operations access the preload
register. TIMx_CCR1 preload value is loaded in the active register at each update event.
Note: These bits can not be modified as long as LOCK level 3 has been programmed (LOCK
bits in TIMx_BDTR register) and CC1S=’00’ (the channel is configured in output).
The PWM mode can be used without validating the preload register only in one pulse
mode (OPM bit set in TIMx_CR1 register). Else the behavior is not guaranteed.