blob: f8b803bf5e68c6b50aee85d73a8329f17694a44a (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
|
// vim: shiftwidth=4 tabstop=4 noexpandtab
#include <libopencm3/stm32/rcc.h>
#include <libopencm3/stm32/gpio.h>
#include <libopencm3/stm32/timer.h>
#include <libopencm3/cm3/nvic.h>
static void clock_init(void);
static void gpio_init(void);
static void nvic_init(void);
static void timer_init(void);
void tim2_isr(void);
void main(void)
{
clock_init();
gpio_init();
nvic_init();
timer_init();
while(1); // wait forever
}
static void clock_init(void)
{
rcc_clock_setup_pll(&rcc_hse_configs[RCC_CLOCK_HSE8_72MHZ]);
rcc_periph_clock_enable(RCC_GPIOC); // for PC13 blinking
rcc_periph_clock_enable(RCC_TIM2); // for timer / counter 2
}
static void gpio_init(void)
{
gpio_set_mode(GPIOC,
GPIO_MODE_OUTPUT_50_MHZ,
GPIO_CNF_OUTPUT_PUSHPULL,
GPIO13);
}
static void nvic_init(void)
{
nvic_enable_irq(NVIC_TIM2_IRQ);
nvic_set_priority(NVIC_TIM2_IRQ, 1);
}
static void timer_init(void)
{
// set LED on
gpio_clear(GPIOC, GPIO13);
// setup timer
timer_set_counter(TIM2, 1);
timer_set_prescaler(TIM2, 1440);
timer_set_period(TIM2, 50000);
timer_enable_irq(TIM2, TIM_DIER_UIE); // set action to trigger interrupt
timer_enable_counter(TIM2);
}
void tim2_isr(void)
{
gpio_toggle(GPIOC, GPIO13);
TIM_SR(TIM2) &= ~TIM_SR_UIF; // clear interrrupt flag
}
|
