RM0444 Rev 5 857/1390
RM0444 Infrared interface (IRTIM)
857
27 Infrared interface (IRTIM)
An infrared interface (IRTIM) for remote control is available on the device. It can be used
with an infrared LED to perform remote control functions.
It uses internal connections with USART1, USART4 (on STM32G071/81/B1/C1xx) or
USART2 (STM32G031/41/51/61xx), TIM16 and TIM17 as shown in Figure 277.
To generate the infrared remote control signals, the IR interface must be enabled and TIM16
channel 1 (TIM16_OC1) and TIM17 channel 1 (TIM17_OC1) must be properly configured to
generate correct waveforms.
The infrared receiver can be implemented easily through a basic input capture mode.
Figure 277. IRTIM internal hardware connections
3. USART4 (on STM32G071/81/B1/C1xx) or USART2 (STM32G031/41/51/61xx).
All standard IR pulse modulation modes can be obtained by programming the two timer
output compare channels.
TIM17 is used to generate the high frequency carrier signal, while TIM16 or alternatively
USART1 or USART4
(a)
generates the modulation envelope according to the setting of the
IR_MOD[1:0] bits in the SYSCFG_CFGR1 register.
The polarity of the output signal from IRTIM is controlled by the IR_POL bit in the
SYSCFG_CFGR1 register and could be inverted by setting of this bit.
The infrared function is output on the IR_OUT pin. The activation of this function is done
through the GPIOx_AFRx register by enabling the related alternate function bit.
The high sink LED driver capability (only available on the PB9 pin) can be activated through
the I2C_PB9_FMP bit in the SYSCFG_CFGR1 register and used to sink the high current
needed to directly control an infrared LED.
a. USART4 (on STM32G071/81/B1/C1xx) or USART2 (STM32G031/41/51/61).
MS44790V2
TIM17_CH1
TIM16_CH1
IRTIM
IR_OUT
USART1
USART4
(1)
IR_MOD[1:0]
IR_POL
To Next Page
Loading...
Need help?
General
