circuitpython/stm/usrsw.c

70 lines
2.1 KiB
C

#include <stm_misc.h>
#include <stm32f4xx_gpio.h>
#include <stm32f4xx_exti.h>
#include <stm32f4xx_syscfg.h>
#include <stm32f4xx_rcc.h>
#include "misc.h"
#include "mpconfig.h"
#include "obj.h"
#include "usrsw.h"
#define PYB_USRSW_PORT (GPIOA)
#define PYB_USRSW_PIN (GPIO_Pin_13)
void switch_init(void) {
// make it an input with pull-up
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.GPIO_Pin = PYB_USRSW_PIN;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_Init(PYB_USRSW_PORT, &GPIO_InitStructure);
// the rest does the EXTI interrupt
/* Enable SYSCFG clock */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);
/* Connect EXTI Line13 to PA13 pin */
SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOA, EXTI_PinSource13);
/* Configure EXTI Line13, rising edge */
EXTI_InitTypeDef EXTI_InitStructure;
EXTI_InitStructure.EXTI_Line = EXTI_Line13;
EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising;
EXTI_InitStructure.EXTI_LineCmd = ENABLE;
EXTI_Init(&EXTI_InitStructure);
/* Enable and set EXTI15_10 Interrupt to the lowest priority */
NVIC_InitTypeDef NVIC_InitStructure;
NVIC_InitStructure.NVIC_IRQChannel = EXTI15_10_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x0F;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x0F;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
}
int switch_get(void) {
if (PYB_USRSW_PORT->IDR & PYB_USRSW_PIN) {
// pulled high, so switch is not pressed
return 0;
} else {
// pulled low, so switch is pressed
return 1;
}
}
/******************************************************************************/
/* Micro Python bindings */
static mp_obj_t pyb_switch(void) {
if (switch_get()) {
return mp_const_true;
} else {
return mp_const_false;
}
}
MP_DEFINE_CONST_FUN_OBJ_0(pyb_switch_obj, pyb_switch);