Tim1/Tim8 Slave Mode Control Register (Timx_Smcr) - ST STM32L4x6 Reference Manual

Advanced-control timers (TIM1/TIM8)
Bit 2 CCUS: Capture/compare control update selection
0: When capture/compare control bits are preloaded (CCPC=1), they are updated by setting
the COMG bit only
1: When capture/compare control bits are preloaded (CCPC=1), they are updated by setting
the COMG bit or when an rising edge occurs on TRGI
Note: This bit acts only on channels that have a complementary output.
Bit 1 Reserved, must be kept at reset value.
Bit 0 CCPC: Capture/compare preloaded control
0: CCxE, CCxNE and OCxM bits are not preloaded
1: CCxE, CCxNE and OCxM bits are preloaded, after having been written, they are updated
only when a commutation event (COM) occurs (COMG bit set or rising edge detected on
TRGI, depending on the CCUS bit).
Note: This bit acts only on channels that have a complementary output.
26.4.3

TIM1/TIM8 slave mode control register (TIMx_SMCR)

Address offset: 0x08
Reset value: 0x0000 0000
31 30 29
Res. Res. Res. Res.
15 14 13
ETP ECE ETPS[1:0]
rw rw rw
Bits 31:17 Reserved, must be kept at reset value.
Bit 16 SMS[3]: Slave mode selection - bit 3
Refer to SMS description - bits2:0
Bit 15 ETP: External trigger polarity
This bit selects whether ETR or ETR is used for trigger operations
0: ETR is non-inverted, active at high level or rising edge.
1: ETR is inverted, active at low level or falling edge.
Bit 14 ECE: External clock enable
This bit enables External clock mode 2.
0: External clock mode 2 disabled
1: External clock mode 2 enabled. The counter is clocked by any active edge on the ETRF
signal.
Note: 1: Setting the ECE bit has the same effect as selecting external clock mode 1 with
816/1693
28 27 26 25
Res. Res. Res.
12 11 10 9
ETF[3:0]
rw rw rw rw
TRGI connected to ETRF (SMS=111 and TS=111).
2: It is possible to simultaneously use external clock mode 2 with the following slave
modes: reset mode, gated mode and trigger mode. Nevertheless, TRGI must not be
connected to ETRF in this case (TS bits must not be 111).
3: If external clock mode 1 and external clock mode 2 are enabled at the same time,
the external clock input is ETRF.
DocID024597 Rev 3
24 23 22 21
Res. Res. Res. Res.
8 7 6 5
MSM TS[2:0]
rw rw rw rw
20 19 18 17
Res. Res. Res. Res.
4 3 2 1
OCCS SMS[2:0]
rw rw rw rw
RM0351
16
SMS[3]
rw
0
rw