STM32W108HBU61TR STMicroelectronics, STM32W108HBU61TR Datasheet - Page 140

• Manufacturer Part Number: STM32W108HBU61TR
• Description: 16/32-BITS MICROS
• Manufacturer: STMicroelectronics
• Series: STM32r

Specifications of STM32W108HBU61TR

• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Applications: IEEE 802.15.4 Wireless
• Processing Unit: Microprocessor
• Operating Supply Voltage (min): 1.18V
• Operating Supply Voltage (typ): 1.25V
• Operating Supply Voltage (max): 1.32V
• Package Type: VFQFPN EP
• Pin Count: 40
• Mounting: Surface Mount
• Rad Hardened: No
• Core Processor: ARM® Cortex-M3™
• Program Memory Type: FLASH (128 kB)
• Controller Series: STM32W
• Ram Size: 8K x 8
• Interface: I²C, SPI, UART/USART
• Number Of I /o: 18
• Voltage - Supply: 1.18 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 40-VFQFN Exposed Pad
• Lead Free Status / Rohs Status: Compliant

General-purpose timers
Note:
140/220
Using one timer to enable the other timer
In this example, the enable of Timer 2 is controlled with the output compare 1 of Timer 1.
Refer to
OC1REF of Timer 1 is high. Both counter clock frequencies are divided by 3 by the
prescaler compared to CK_INT (fCK_CNT = fCK_INT /3).
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The counter 2 clock is not synchronized with counter 1, this mode only affects the Timer 2
counter enable signal.
Figure 46. Gating Timer 2 with OC1REF of Timer 1
In the example in
being started. So they start counting from their current value. It is possible to start from a
given value by resetting both timers before starting Timer 1, then writing the desired value in
the timer counters. The timers can easily be reset by software using the TIM_UG bit in the
TIMx_EGR registers.
The next example, synchronizes Timer 1 and Timer 2. Timer 1 is the master and starts from
0. Timer 2 is the slave and starts from 0xE7. The prescaler ratio is the same for both timers.
Timer 2 stops when Timer 1 is disabled by writing 0 to the TIM_CEN bit in the TIM1_CR1
register:
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Configure Timer 1 in master mode to send its Output Compare Reference (OC1REF)
signal as trigger output (TIM_MMS = 100 in the TIM1_CR2 register).
Configure the Timer 1 OC1REF waveform (TIM1_CCMR1 register).
Configure Timer 2 to get the input trigger from Timer 1 (TIM_TS = 000 in the
TIM2_SMCR register).
Configure Timer 2 in Gated mode (TIM_SMS = 101 in the TIM2_SMCR register).
Enable Timer 2 by writing 1 in the TIM_CEN bit (TIM2_CR1 register).
Start Timer 1 by writing 1 in the TIM_CEN bit (TIM1_CR1 register).
Configure Timer 1 in master mode to send its Output Compare Reference (OC1REF)
signal as trigger output (TIM_MMS = 100 in the TIM1_CR2 register).
Configure the Timer 1 OC1REF waveform (TIM1_CCMR1 register).
Configure Timer 2 to get the input trigger from Timer 1 (TIM_TS = 000 in the
TIM2_SMCR register).
Configure Timer 2 in gated mode (TIM_SMS = 101 in the TIM2_SMCR register).
Reset Timer 1 by writing 1 in the TIM_UG bit (TIM1_EGR register).
Figure 45
Figure
STM32W108HB, STM32W108CC, STM32W108CB and STM32W108CZ
for connections. Timer 2 counts on the divided internal clock only when
46, the Timer 2 counter and prescaler are not initialized before
Doc ID 16252 Rev 9