Hello World example for interfacing up to four rotary encoders to the STM32's timer/counter hardware, without interrupts.
EncoderMspInitF1.cpp
00001 #include "mbed.h" 00002 /* 00003 * HAL_TIM_Encoder_MspInit() 00004 * Overrides the __weak function stub in stm32f1xx_hal_tim.h 00005 * 00006 * Edit the below for your preferred pin wiring & pullup/down 00007 * I have encoder common at 3V3, using GPIO_PULLDOWN on inputs. 00008 * Encoder A&B outputs connected directly to GPIOs. 00009 * 00010 * http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/CD00161566.pdf 00011 * Table 5 has GPIO alternate function pinout mappings. 00012 * 00013 * TIM1_CH1: default PA_8, remap PE_9 00014 * TIM1_CH2: default PA_9, remap PE_11 00015 * 00016 * TIM2_CH1: default PA_0 00017 * TIM2_CH2: default PA_1, remap PB_3 00018 * 00019 * TIM3_CH1: default PA_6, remap PB_4, PC_6 00020 * TIM3_CH2: default PA_7, remap PB_5, PC_7 00021 * 00022 * TIM4_CH1: default PB_6, remap PD_12 00023 * TIM4_CH2: default PB_7, remap PD_13 00024 * 00025 * NB one of these timers will be the employed by mbed as systick, unavailable as encoder. 00026 */ 00027 00028 #ifdef TARGET_STM32F1 00029 void HAL_TIM_Encoder_MspInit(TIM_HandleTypeDef *htim) 00030 { 00031 GPIO_InitTypeDef GPIO_InitStruct; 00032 00033 if (htim->Instance == TIM1) { //PA8 PA9 = Nucleo D7 D8 00034 __TIM1_CLK_ENABLE(); 00035 __GPIOA_CLK_ENABLE(); 00036 GPIO_InitStruct.Pin = GPIO_PIN_8 | GPIO_PIN_9; 00037 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP; 00038 GPIO_InitStruct.Pull = GPIO_PULLDOWN; 00039 GPIO_InitStruct.Speed = GPIO_SPEED_HIGH; 00040 // GPIO_InitStruct.Alternate = GPIO_AF1_TIM1; 00041 HAL_GPIO_Init(GPIOA, &GPIO_InitStruct); 00042 } 00043 else if (htim->Instance == TIM2) { //PA0 PA1 = Nucleo A0 A1 00044 __TIM2_CLK_ENABLE(); 00045 __GPIOA_CLK_ENABLE(); 00046 GPIO_InitStruct.Pin = GPIO_PIN_0 | GPIO_PIN_1; 00047 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP; 00048 GPIO_InitStruct.Pull = GPIO_PULLDOWN; 00049 GPIO_InitStruct.Speed = GPIO_SPEED_HIGH; 00050 // GPIO_InitStruct.Alternate = GPIO_AF1_TIM2; 00051 HAL_GPIO_Init(GPIOA, &GPIO_InitStruct); 00052 } 00053 else if (htim->Instance == TIM3) { //PA6 PA7 = Nucleo D12 D11 00054 __TIM3_CLK_ENABLE(); 00055 __GPIOA_CLK_ENABLE(); 00056 GPIO_InitStruct.Pin = GPIO_PIN_6 | GPIO_PIN_7; 00057 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP; 00058 GPIO_InitStruct.Pull = GPIO_PULLDOWN; 00059 GPIO_InitStruct.Speed = GPIO_SPEED_HIGH; 00060 // GPIO_InitStruct.Alternate = GPIO_AF2_TIM3; 00061 HAL_GPIO_Init(GPIOA, &GPIO_InitStruct); 00062 } 00063 else if (htim->Instance == TIM4) { // PB6 PB7 = Nucleo D10 MORPHO PB7 00064 __TIM4_CLK_ENABLE(); 00065 __GPIOB_CLK_ENABLE(); 00066 GPIO_InitStruct.Pin = GPIO_PIN_6 | GPIO_PIN_7; 00067 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP; 00068 GPIO_InitStruct.Pull = GPIO_PULLDOWN; 00069 GPIO_InitStruct.Speed = GPIO_SPEED_HIGH; 00070 // GPIO_InitStruct.Alternate = GPIO_AF2_TIM4; 00071 HAL_GPIO_Init(GPIOB, &GPIO_InitStruct); 00072 } 00073 } 00074 #endif
Generated on Tue Jul 12 2022 18:53:57 by 1.7.2