STM32W108CB STMicroelectronics, STM32W108CB Datasheet - Page 141

• Manufacturer Part Number: STM32W108CB
• Description: High-performance, IEEE 802.15.4 wireless system-on-chip with embedded Flash memory
• Manufacturer: STMicroelectronics

Specifications of STM32W108CB

• Receive Current (w/ Cpu): 27 mA
• Transmit Current (w/ Cpu, +3 Dbm Tx): 31 mA
• Low Deep Sleep Current, With Retained Ram And Gpio: 400 nA/800 nA with/without sleep timer
• Standard Arm Debug Capabilities: Flash patch & breakpoint; data watchpoint & trace; instrumentation trace macrocell
• Single Voltage Operation: 2.1-3.6 V with internal 1.8 V and 1.25 V regulators

STM32W108HB STM32W108CC STM32W108CB STM32W108CZ
10.1.13
Timers and external trigger synchronization
The timers can be synchronized with an external trigger in several modes: Reset mode,
Gated mode, and Trigger mode.
Slave mode: Reset mode
Reset mode reinitializes the counter and its prescaler in response to an event on a trigger
input. Moreover, if the TIM_URS bit in the TIMx_CR1 register is low, an update event is
generated. Then all the buffered registers (TIMx_ARR, TIMx_CCRy) are updated.
In the following example, the up-counter is cleared in response to a rising edge on the TI1
input:
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The counter starts counting on the internal clock, then behaves normally until the TI1 rising
edge. When TI1 rises, the counter is cleared and restarts from 0. In the meantime, the
trigger flag is set (the INT_TIMTIF bit in the INT_TIMxFLAG register) and an interrupt
request can be sent if enabled (depending on the INT_TIMTIF bit in the INT_TIMxCFG
register).
Figure 41
between the rising edge on TI1 and the actual reset of the counter is due to the
resynchronization circuit on the TI1 input.
Figure 41. Control circuit in Reset mode
Configure the channel 1 to detect rising edges on TI1: Configure the input filter
duration. In this example, no filter is required so TIM_IC1F = 0000. The capture
prescaler is not used for triggering, so it is not configured. The TIM_CC1S bits select
the input capture source only, TIM_CC1S = 01 in the TIMx_CCMR1 register. Write
TIM_CC1P = 0 in the TIMx_CCER register to validate the polarity, and detect rising
edges only.
Configure the timer in Reset mode by writing TIM_SMS = 100 in the TIMx_SMCR
register. Select TI1 as the input source by writing TIM_TS = 101 in the TIMx_SMCR
register.
Start the counter by writing TIM_CEN = 1 in the TIMx_CR1 register.
shows this behavior when the auto-reload register TIMx_ARR = 0x36. The delay
Doc ID 16252 Rev 13
General-purpose timers
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