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OrsoEric/main.cpp

Created Jul 5, 2020
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GD32VF103 Longan Nano PA8 interrupt Minimal Example
#include <gd32vf103.h>
#define EVER (;;)
void init()
{
//Clock the GPIO banks
rcu_periph_clock_enable(RCU_GPIOA);
rcu_periph_clock_enable(RCU_GPIOC);
//Setup the R, G and B LEDs
gpio_init(GPIOA, GPIO_MODE_OUT_PP, GPIO_OSPEED_50MHZ,GPIO_PIN_1);
gpio_init(GPIOA, GPIO_MODE_OUT_PP, GPIO_OSPEED_50MHZ,GPIO_PIN_2);
gpio_init(GPIOA, GPIO_MODE_IN_FLOATING, GPIO_OSPEED_50MHZ,GPIO_PIN_8);
//Setup the boot button
gpio_init(GPIOC, GPIO_MODE_OUT_PP, GPIO_OSPEED_50MHZ,GPIO_PIN_13);
//Initialize the LEDs to: OFF
gpio_bit_set(GPIOC,GPIO_PIN_13);
gpio_bit_set(GPIOA,GPIO_PIN_1);
gpio_bit_set(GPIOA,GPIO_PIN_2);
//Clock the alternate functions
rcu_periph_clock_enable(RCU_AF);
//Initialize the ECLIC IRQ lines
eclic_priority_group_set(ECLIC_PRIGROUP_LEVEL3_PRIO1);
eclic_irq_enable(EXTI5_9_IRQn, 1, 1);
//Initialize the EXTI. IRQ can be generated from GPIO edge detectors
gpio_exti_source_select(GPIO_PORT_SOURCE_GPIOA, GPIO_PIN_SOURCE_8);
exti_init(EXTI_8, EXTI_INTERRUPT, EXTI_TRIG_BOTH);
//Clear interrupt flag. Ensure no spurious execution at start
exti_interrupt_flag_clear(EXTI_8);
//Enable the interrupts. From now on interrupt handlers can be executed
eclic_global_interrupt_enable();
return;
}
extern "C"
void EXTI5_9_IRQHandler()
{
//If: interrupt from PA8 boot button
if (exti_interrupt_flag_get(EXTI_8) != RESET)
{
//Clear the interrupt from PA8 boot button
exti_interrupt_flag_clear(EXTI_8);
//Toggle the blue led
gpio_bit_write(GPIOA, GPIO_PIN_2, (bit_status)(1-gpio_input_bit_get(GPIOA, GPIO_PIN_2)));
}
//Default: interrupt from an unhandled GPIO
else
{
//Do nothing (should clear the interrupt flags)
}
}
void delay_us(unsigned int us)
{
uint64_t start_mtime, delta_mtime;
uint64_t tmp = get_timer_value();
do
{
start_mtime = get_timer_value();
}
while (start_mtime == tmp);
do
{
delta_mtime = get_timer_value() - start_mtime;
}
while(delta_mtime <(SystemCoreClock/4000000.0 *us ));
return;
}
int main()
{
init();
for EVER
{
//Toggle the RED LED
gpio_bit_write(GPIOC, GPIO_PIN_13, (bit_status)(1-gpio_input_bit_get(GPIOC, GPIO_PIN_13)));
//2Hz blink
delay_us(250000);
}
return 0;
}
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