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#include "project.h"
#define P1 (GPIO11)
#define P1_PORT GPIOD
#define T (GPIO12)
#define T_PORT GPIOD
static Event_ring dcf77_ring;
uint64_t dcf77_last_second;
void exti15_10_isr (void)
{
uint32_t now = SCS_DWT_CYCCNT;
int v;
v = !!gpio_get (T_PORT, T);
nvic_disable_irq (NVIC_EXTI15_10_IRQ);
exti_reset_request (EXTI12);
dcf77_ring.events[dcf77_ring.tx_ptr].when = now;
dcf77_ring.events[dcf77_ring.tx_ptr].value = v;
dcf77_ring.tx_ptr = (dcf77_ring.tx_ptr + 1) & ERING_MASK;
nvic_enable_irq (NVIC_EXTI15_10_IRQ);
}
static uint8_t bits[60];
static void process_bits (uint64_t abs)
{
UTC u;
EPOCH dcf77_time;
if (bits[0]) return;
if (!bits[20]) return;
if (!check_parity (bits, 21, 27, bits[28])) return;
if (!check_parity (bits, 29, 34, bits[35])) return;
if (!check_parity (bits, 36, 57, bits[58])) return;
u.jday = 0;
u.year = le_bcd (bits, 50, 57);
u.month = le_bcd (bits, 45, 49);
u.mday = bcd (bits, 36, 41);
u.hour = bcd (bits, 29, 34);
u.minute = bcd (bits, 21, 27);
u.second = 58;
u.nanosecond = 0;
dcf77_time = time_utc_to_epoch (u);
dcf77_time.s -= 58;
#if 0
pll_set_offset (dcf77_time, abs);
#endif
printf ("DCF77: Next minute is: %02d-%02d-%02d %02d:%02d\r\n", u.year, u.month, u.mday, u.hour, u.minute);
time_print_epoch ("DCF77: ", dcf77_time);
dump_bits ("dcf77", bits);
}
static void report_bit (uint64_t abs, int second, int b)
{
if ((second < 0) || (second > 58)) return;
bits[second] = b;
// printf("DCF77: bits[%d]=%d\r\n",second,b);
if (second == 58) process_bits (abs);
}
static void report_time (uint64_t abs)
{
#if 1
EPOCH e = pll_decompose (abs);
time_print_epoch ("DCF77: ", e);
#endif
}
void dcf77_dispatch (void)
{
static uint32_t last_0, last_1, last_s;
static int second, bit, had_m;
uint32_t pulse_w, offset;
static uint64_t abs;
int is_s = 0;
uint32_t now;
int v;
if (dcf77_ring.rx_ptr == dcf77_ring.tx_ptr) return;
v = dcf77_ring.events[dcf77_ring.rx_ptr].value;
now = dcf77_ring.events[dcf77_ring.rx_ptr].when;
dcf77_ring.rx_ptr = (dcf77_ring.rx_ptr + 1) & ERING_MASK;
if (v) {
pulse_w = now - last_0;
pulse_w /= (HZ / 1000);
last_1 = now;
if (pulse_w > 300) {
last_s = now;
is_s = 1;
second++;
}
if (pulse_w > 1300) {
had_m = 1;
second = 0;
}
} else {
pulse_w = now - last_1;
pulse_w /= (HZ / 1000);
if (pulse_w > 150)
bit = 1;
else
bit = 0;
if (had_m)
report_bit (abs, second, bit);
last_0 = now;
}
offset = now - last_s;
offset /= (HZ / 1000);
if (is_s) {
abs = abs_extend (now);
dcf77_last_second = abs;
//pll_dispatch (abs);
if (time_known)
report_time (abs);
}
}
void
dcf77_init (void)
{
MAP_INPUT (T);
MAP_OUTPUT_PP (P1);
gpio_clear (P1_PORT, P1);
exti_select_source (EXTI12, T_PORT);
exti_set_trigger (EXTI12, EXTI_TRIGGER_BOTH);
exti_enable_request (EXTI12);
nvic_enable_irq (NVIC_EXTI15_10_IRQ);
}
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