ESP32-PaxCounter/src/timekeeper.cpp
2019-08-18 22:13:42 +02:00

321 lines
9.5 KiB
C++

#include "timekeeper.h"
#include "paxcounter.conf"
#if !(HAS_LORA)
#if (TIME_SYNC_LORASERVER)
#error TIME_SYNC_LORASERVER defined, but device has no LORA configured
#elif (TIME_SYNC_LORAWAN)
#error TIME_SYNC_LORAWAN defined, but device has no LORA configured
#endif
#endif
// Local logging tag
static const char TAG[] = __FILE__;
// symbol to display current time source
const char timeSetSymbols[] = {'G', 'R', 'L', '?'};
#ifdef HAS_IF482
HardwareSerial IF482(2); // use UART #2 (#1 may be in use for serial GPS)
#endif
Ticker timesyncer;
void timeSync() { xTaskNotify(irqHandlerTask, TIMESYNC_IRQ, eSetBits); }
void calibrateTime(void) {
time_t t = 0;
uint16_t t_msec = 0;
#if (HAS_GPS)
// fetch recent time from last NMEA record
t = fetch_gpsTime(&t_msec);
if (t) {
timeSource = _gps;
goto finish;
}
#endif
// kick off asychronous Lora timeserver timesync if we have
#if (HAS_LORA) && (TIME_SYNC_LORASERVER)
send_timesync_req();
// kick off asychronous lora network sync if we have
#elif (HAS_LORA) && (TIME_SYNC_LORAWAN)
LMIC_requestNetworkTime(user_request_network_time_callback, &userUTCTime);
#endif
// no time from GPS -> fallback to RTC time while trying lora sync
#ifdef HAS_RTC
t = get_rtctime();
if (t) {
timeSource = _rtc;
goto finish;
}
#endif
goto finish;
finish:
setMyTime((uint32_t)t, t_msec, timeSource); // set time
} // calibrateTime()
// adjust system time, calibrate RTC and RTC_INT pps
void IRAM_ATTR setMyTime(uint32_t t_sec, uint16_t t_msec,
timesource_t mytimesource) {
// called with invalid timesource?
if (mytimesource == _unsynced)
return;
// increment t_sec only if t_msec > 1000
time_t time_to_set = (time_t)(t_sec + t_msec / 1000);
// do we have a valid time?
if (timeIsValid(time_to_set)) {
// if we have msec fraction, then wait until top of second with
// millisecond precision
if (t_msec % 1000) {
time_to_set++;
vTaskDelay(pdMS_TO_TICKS(1000 - t_msec % 1000));
}
ESP_LOGD(TAG, "[%0.3f] UTC epoch time: %d.%03d sec", millis() / 1000.0,
time_to_set, t_msec % 1000);
// if we have got an external timesource, set RTC time and shift RTC_INT pulse
// to top of second
#ifdef HAS_RTC
if ((mytimesource == _gps) || (mytimesource == _lora))
set_rtctime(time_to_set);
#endif
// if we have a software pps timer, shift it to top of second
#if (!defined GPS_INT && !defined RTC_INT)
timerWrite(ppsIRQ, 0); // reset pps timer
CLOCKIRQ(); // fire clock pps, this advances time 1 sec
#endif
setTime(time_to_set); // set the time on top of second
timeSource = mytimesource; // set global variable
timesyncer.attach(TIME_SYNC_INTERVAL * 60, timeSync);
ESP_LOGI(TAG, "[%0.3f] Timesync finished, time was set | source: %c",
millis() / 1000.0, timeSetSymbols[timeSource]);
} else {
timesyncer.attach(TIME_SYNC_INTERVAL_RETRY * 60, timeSync);
ESP_LOGI(TAG, "[%0.3f] Timesync failed, invalid time fetched | source: %c",
millis() / 1000.0, timeSetSymbols[timeSource]);
}
}
// helper function to setup a pulse per second for time synchronisation
uint8_t timepulse_init() {
// use time pulse from GPS as time base with fixed 1Hz frequency
#ifdef GPS_INT
// setup external interupt pin for rising edge GPS INT
pinMode(GPS_INT, INPUT_PULLDOWN);
// setup external rtc 1Hz clock as pulse per second clock
ESP_LOGI(TAG, "Timepulse: external (GPS)");
return 1; // success
// use pulse from on board RTC chip as time base with fixed frequency
#elif defined RTC_INT
// setup external interupt pin for falling edge RTC INT
pinMode(RTC_INT, INPUT_PULLUP);
// setup external rtc 1Hz clock as pulse per second clock
if (I2C_MUTEX_LOCK()) {
Rtc.SetSquareWavePinClockFrequency(DS3231SquareWaveClock_1Hz);
Rtc.SetSquareWavePin(DS3231SquareWavePin_ModeClock);
I2C_MUTEX_UNLOCK();
ESP_LOGI(TAG, "Timepulse: external (RTC)");
return 1; // success
} else {
ESP_LOGE(TAG, "RTC initialization error, I2C bus busy");
return 0; // failure
}
return 1; // success
#else
// use ESP32 hardware timer as time base with adjustable frequency
ppsIRQ = timerBegin(1, 8000, true); // set 80 MHz prescaler to 1/10000 sec
timerAlarmWrite(ppsIRQ, 10000, true); // 1000ms
ESP_LOGI(TAG, "Timepulse: internal (ESP32 hardware timer)");
return 1; // success
#endif
} // timepulse_init
void timepulse_start(void) {
#ifdef GPS_INT // start external clock gps pps line
attachInterrupt(digitalPinToInterrupt(GPS_INT), CLOCKIRQ, RISING);
#elif defined RTC_INT // start external clock rtc
attachInterrupt(digitalPinToInterrupt(RTC_INT), CLOCKIRQ, FALLING);
#else // start internal clock esp32 hardware timer
timerAttachInterrupt(ppsIRQ, &CLOCKIRQ, true);
timerAlarmEnable(ppsIRQ);
#endif
// start cyclic time sync
timeSync(); // init systime by RTC or GPS or LORA
timesyncer.attach(TIME_SYNC_INTERVAL * 60, timeSync);
}
// interrupt service routine triggered by either pps or esp32 hardware timer
void IRAM_ATTR CLOCKIRQ(void) {
BaseType_t xHigherPriorityTaskWoken = pdFALSE;
SyncToPPS(); // advance systime, see microTime.h
// advance wall clock, if we have
#if (defined HAS_IF482 || defined HAS_DCF77)
xTaskNotifyFromISR(ClockTask, uint32_t(now()), eSetBits,
&xHigherPriorityTaskWoken);
#endif
// flip time pulse ticker, if needed
#ifdef HAS_DISPLAY
#if (defined GPS_INT || defined RTC_INT)
TimePulseTick = !TimePulseTick; // flip pulse ticker
#endif
#endif
// yield only if we should
if (xHigherPriorityTaskWoken)
portYIELD_FROM_ISR();
}
// helper function to check plausibility of a time
time_t timeIsValid(time_t const t) {
// is it a time in the past? we use compile date to guess
return (t >= compiledUTC() ? t : 0);
}
// helper function to convert compile time to UTC time
time_t compiledUTC(void) {
static time_t t = myTZ.toUTC(RtcDateTime(__DATE__, __TIME__).Epoch32Time());
return t;
}
// helper function to calculate serial transmit time
TickType_t tx_Ticks(uint32_t framesize, unsigned long baud, uint32_t config,
int8_t rxPin, int8_t txPins) {
uint32_t databits = ((config & 0x0c) >> 2) + 5;
uint32_t stopbits = ((config & 0x20) >> 5) + 1;
uint32_t txTime = (databits + stopbits + 1) * framesize * 1000.0 / baud;
// +1 for the startbit
return round(txTime);
}
#if (defined HAS_IF482 || defined HAS_DCF77)
#if (defined HAS_DCF77 && defined HAS_IF482)
#error You must define at most one of IF482 or DCF77!
#endif
void clock_init(void) {
// setup clock output interface
#ifdef HAS_IF482
IF482.begin(HAS_IF482);
#elif defined HAS_DCF77
pinMode(HAS_DCF77, OUTPUT);
#endif
userUTCTime = now();
xTaskCreatePinnedToCore(clock_loop, // task function
"clockloop", // name of task
2048, // stack size of task
(void *)&userUTCTime, // start time as task parameter
4, // priority of the task
&ClockTask, // task handle
1); // CPU core
assert(ClockTask); // has clock task started?
} // clock_init
void clock_loop(void *taskparameter) { // ClockTask
// caveat: don't use now() in this task, it will cause a race condition
// due to concurrent access to i2c bus when reading/writing from/to rtc chip!
#define nextmin(t) (t + DCF77_FRAME_SIZE + 1) // next minute
#ifdef HAS_TWO_LED
static bool led1_state = false;
#endif
uint32_t printtime;
time_t t = *((time_t *)taskparameter), last_printtime = 0; // UTC time seconds
#ifdef HAS_DCF77
uint8_t *DCFpulse; // pointer on array with DCF pulse bits
DCFpulse = DCF77_Frame(nextmin(t)); // load first DCF frame before start
#elif defined HAS_IF482
static TickType_t txDelay = pdMS_TO_TICKS(1000 - IF482_SYNC_FIXUP) -
tx_Ticks(IF482_FRAME_SIZE, HAS_IF482);
#endif
// output the next second's pulse/telegram after pps arrived
for (;;) {
// wait for timepulse and store UTC time in seconds got
xTaskNotifyWait(0x00, ULONG_MAX, &printtime, portMAX_DELAY);
t = time_t(printtime);
// no confident or no recent time -> suppress clock output
if ((timeStatus() == timeNotSet) || !(timeIsValid(t)) ||
(t == last_printtime))
continue;
#if defined HAS_IF482
// wait until moment to fire. Normally we won't get notified during this
// timespan, except when next pps pulse arrives while waiting, because pps
// was adjusted by recent time sync
if (xTaskNotifyWait(0x00, ULONG_MAX, &printtime, txDelay) == pdTRUE)
t = time_t(printtime); // new adjusted UTC time seconds
// send IF482 telegram
IF482.print(IF482_Frame(t + 1)); // note: telegram is for *next* second
#elif defined HAS_DCF77
if (second(t) == DCF77_FRAME_SIZE - 1) // is it time to load new frame?
DCFpulse = DCF77_Frame(nextmin(t)); // generate frame for next minute
if (minute(nextmin(t)) == // do we still have a recent frame?
DCFpulse[DCF77_FRAME_SIZE]) // (timepulses could be missed!)
DCF77_Pulse(t, DCFpulse); // then output current second's pulse
// else we have no recent frame, thus suppressing clock output
#endif
// pps blink on secondary LED if we have one
#ifdef HAS_TWO_LED
if (led1_state)
switch_LED1(LED_OFF);
else
switch_LED1(LED_ON);
led1_state = !led1_state;
#endif
last_printtime = t;
} // for
} // clock_loop()
#endif // HAS_IF482 || defined HAS_DCF77