David Lowe / Nucleo_Hello_Encoder

Hello World example for interfacing up to four rotary encoders to the STM32's timer/counter hardware, without interrupts.

Dependencies:   mbed-dev

Encoder/EncoderMspInitF1.cpp@1:cd7b42c99ff8, 2015-10-04 (annotated)

Committer:
gregeric
Date:
Sun Oct 04 11:58:58 2015 +0000
Revision:
1:cd7b42c99ff8
Added more targets, use HAL macros to read counter value & direction.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
gregeric 1:cd7b42c99ff8 1 #include "mbed.h"
gregeric 1:cd7b42c99ff8 2 /*
gregeric 1:cd7b42c99ff8 3 * HAL_TIM_Encoder_MspInit()
gregeric 1:cd7b42c99ff8 4 * Overrides the __weak function stub in stm32f1xx_hal_tim.h
gregeric 1:cd7b42c99ff8 5 *
gregeric 1:cd7b42c99ff8 6 * Edit the below for your preferred pin wiring & pullup/down
gregeric 1:cd7b42c99ff8 7 * I have encoder common at 3V3, using GPIO_PULLDOWN on inputs.
gregeric 1:cd7b42c99ff8 8 * Encoder A&B outputs connected directly to GPIOs.
gregeric 1:cd7b42c99ff8 9 *
gregeric 1:cd7b42c99ff8 10 * http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/CD00161566.pdf
gregeric 1:cd7b42c99ff8 11 * Table 5 has GPIO alternate function pinout mappings.
gregeric 1:cd7b42c99ff8 12 *
gregeric 1:cd7b42c99ff8 13 * TIM1_CH1: default PA_8, remap PE_9
gregeric 1:cd7b42c99ff8 14 * TIM1_CH2: default PA_9, remap PE_11
gregeric 1:cd7b42c99ff8 15 *
gregeric 1:cd7b42c99ff8 16 * TIM2_CH1: default PA_0
gregeric 1:cd7b42c99ff8 17 * TIM2_CH2: default PA_1, remap PB_3
gregeric 1:cd7b42c99ff8 18 *
gregeric 1:cd7b42c99ff8 19 * TIM3_CH1: default PA_6, remap PB_4, PC_6
gregeric 1:cd7b42c99ff8 20 * TIM3_CH2: default PA_7, remap PB_5, PC_7
gregeric 1:cd7b42c99ff8 21 *
gregeric 1:cd7b42c99ff8 22 * TIM4_CH1: default PB_6, remap PD_12
gregeric 1:cd7b42c99ff8 23 * TIM4_CH2: default PB_7, remap PD_13
gregeric 1:cd7b42c99ff8 24 *
gregeric 1:cd7b42c99ff8 25 * NB one of these timers will be the employed by mbed as systick, unavailable as encoder.
gregeric 1:cd7b42c99ff8 26 */
gregeric 1:cd7b42c99ff8 27
gregeric 1:cd7b42c99ff8 28 #ifdef TARGET_STM32F1
gregeric 1:cd7b42c99ff8 29 void HAL_TIM_Encoder_MspInit(TIM_HandleTypeDef *htim)
gregeric 1:cd7b42c99ff8 30 {
gregeric 1:cd7b42c99ff8 31 GPIO_InitTypeDef GPIO_InitStruct;
gregeric 1:cd7b42c99ff8 32
gregeric 1:cd7b42c99ff8 33 if (htim->Instance == TIM1) { //PA8 PA9 = Nucleo D7 D8
gregeric 1:cd7b42c99ff8 34 __TIM1_CLK_ENABLE();
gregeric 1:cd7b42c99ff8 35 __GPIOA_CLK_ENABLE();
gregeric 1:cd7b42c99ff8 36 GPIO_InitStruct.Pin = GPIO_PIN_8 | GPIO_PIN_9;
gregeric 1:cd7b42c99ff8 37 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
gregeric 1:cd7b42c99ff8 38 GPIO_InitStruct.Pull = GPIO_PULLDOWN;
gregeric 1:cd7b42c99ff8 39 GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;
gregeric 1:cd7b42c99ff8 40 // GPIO_InitStruct.Alternate = GPIO_AF1_TIM1;
gregeric 1:cd7b42c99ff8 41 HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
gregeric 1:cd7b42c99ff8 42 }
gregeric 1:cd7b42c99ff8 43 else if (htim->Instance == TIM2) { //PA0 PA1 = Nucleo A0 A1
gregeric 1:cd7b42c99ff8 44 __TIM2_CLK_ENABLE();
gregeric 1:cd7b42c99ff8 45 __GPIOA_CLK_ENABLE();
gregeric 1:cd7b42c99ff8 46 GPIO_InitStruct.Pin = GPIO_PIN_0 | GPIO_PIN_1;
gregeric 1:cd7b42c99ff8 47 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
gregeric 1:cd7b42c99ff8 48 GPIO_InitStruct.Pull = GPIO_PULLDOWN;
gregeric 1:cd7b42c99ff8 49 GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;
gregeric 1:cd7b42c99ff8 50 // GPIO_InitStruct.Alternate = GPIO_AF1_TIM2;
gregeric 1:cd7b42c99ff8 51 HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
gregeric 1:cd7b42c99ff8 52 }
gregeric 1:cd7b42c99ff8 53 else if (htim->Instance == TIM3) { //PA6 PA7 = Nucleo D12 D11
gregeric 1:cd7b42c99ff8 54 __TIM3_CLK_ENABLE();
gregeric 1:cd7b42c99ff8 55 __GPIOA_CLK_ENABLE();
gregeric 1:cd7b42c99ff8 56 GPIO_InitStruct.Pin = GPIO_PIN_6 | GPIO_PIN_7;
gregeric 1:cd7b42c99ff8 57 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
gregeric 1:cd7b42c99ff8 58 GPIO_InitStruct.Pull = GPIO_PULLDOWN;
gregeric 1:cd7b42c99ff8 59 GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;
gregeric 1:cd7b42c99ff8 60 // GPIO_InitStruct.Alternate = GPIO_AF2_TIM3;
gregeric 1:cd7b42c99ff8 61 HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
gregeric 1:cd7b42c99ff8 62 }
gregeric 1:cd7b42c99ff8 63 else if (htim->Instance == TIM4) { // PB6 PB7 = Nucleo D10 MORPHO PB7
gregeric 1:cd7b42c99ff8 64 __TIM4_CLK_ENABLE();
gregeric 1:cd7b42c99ff8 65 __GPIOB_CLK_ENABLE();
gregeric 1:cd7b42c99ff8 66 GPIO_InitStruct.Pin = GPIO_PIN_6 | GPIO_PIN_7;
gregeric 1:cd7b42c99ff8 67 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
gregeric 1:cd7b42c99ff8 68 GPIO_InitStruct.Pull = GPIO_PULLDOWN;
gregeric 1:cd7b42c99ff8 69 GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;
gregeric 1:cd7b42c99ff8 70 // GPIO_InitStruct.Alternate = GPIO_AF2_TIM4;
gregeric 1:cd7b42c99ff8 71 HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
gregeric 1:cd7b42c99ff8 72 }
gregeric 1:cd7b42c99ff8 73 }
gregeric 1:cd7b42c99ff8 74 #endif