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

Dependencies:   mbed-dev

Committer:
gregeric
Date:
Sun Oct 04 11:58:58 2015 +0000
Revision:
1:cd7b42c99ff8
Parent:
0:ee5cb967aa17
Added more targets, use HAL macros to read counter value & direction.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
gregeric 0:ee5cb967aa17 1 #include "mbed.h"
gregeric 0:ee5cb967aa17 2 /*
gregeric 0:ee5cb967aa17 3 * HAL_TIM_Encoder_MspInit()
gregeric 0:ee5cb967aa17 4 * Overrides the __weak function stub in stm32f4xx_hal_tim.h
gregeric 0:ee5cb967aa17 5 *
gregeric 0:ee5cb967aa17 6 * Edit the below for your preferred pin wiring & pullup/down
gregeric 0:ee5cb967aa17 7 * I have encoder common at 3V3, using GPIO_PULLDOWN on inputs.
gregeric 0:ee5cb967aa17 8 * Encoder A&B outputs connected directly to GPIOs.
gregeric 0:ee5cb967aa17 9 *
gregeric 0:ee5cb967aa17 10 */
gregeric 0:ee5cb967aa17 11
gregeric 0:ee5cb967aa17 12 #ifdef TARGET_STM32L0
gregeric 0:ee5cb967aa17 13 void HAL_TIM_Encoder_MspInit(TIM_HandleTypeDef *htim)
gregeric 0:ee5cb967aa17 14 {
gregeric 0:ee5cb967aa17 15 GPIO_InitTypeDef GPIO_InitStruct;
gregeric 0:ee5cb967aa17 16
gregeric 0:ee5cb967aa17 17 if (htim->Instance == TIM2) { //PA0 PA1 = Nucleo A0 A1
gregeric 0:ee5cb967aa17 18 __TIM2_CLK_ENABLE();
gregeric 0:ee5cb967aa17 19 __GPIOA_CLK_ENABLE();
gregeric 0:ee5cb967aa17 20 GPIO_InitStruct.Pin = GPIO_PIN_0 | GPIO_PIN_1;
gregeric 0:ee5cb967aa17 21 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
gregeric 0:ee5cb967aa17 22 GPIO_InitStruct.Pull = GPIO_PULLDOWN;
gregeric 0:ee5cb967aa17 23 GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;
gregeric 0:ee5cb967aa17 24 GPIO_InitStruct.Alternate = GPIO_AF1_TIM2;
gregeric 0:ee5cb967aa17 25 HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
gregeric 0:ee5cb967aa17 26 }
gregeric 0:ee5cb967aa17 27 }
gregeric 0:ee5cb967aa17 28 #endif