From e1b6d9a04c94b4f995770b6d7ef73fca5d56b1c7 Mon Sep 17 00:00:00 2001 From: Klaus K Wilting Date: Thu, 7 Feb 2019 20:39:32 +0100 Subject: [PATCH] DCF77 optimizations --- include/dcf77.h | 1 + src/dcf77.cpp | 215 ++++++++++++++++++++++++-------------------- src/paxcounter.conf | 3 +- 3 files changed, 120 insertions(+), 99 deletions(-) diff --git a/include/dcf77.h b/include/dcf77.h index f9a64e61..eef10541 100644 --- a/include/dcf77.h +++ b/include/dcf77.h @@ -17,5 +17,6 @@ void DCF_Out(uint8_t startsec); void generateTimeframe(time_t t); void set_DCF77_pin(dcf_pinstate state); uint8_t dec2bcd(uint8_t dec, uint8_t startpos, uint8_t endpos, uint8_t pArray[]); +uint8_t sync_clock(time_t t); #endif \ No newline at end of file diff --git a/src/dcf77.cpp b/src/dcf77.cpp index f5bd53ec..579b1785 100644 --- a/src/dcf77.cpp +++ b/src/dcf77.cpp @@ -44,8 +44,7 @@ int dcf77_init(void) { assert(DCF77Task); // has dcf77 task started? - // if we have hardware pps signal we use it as precise time base -#ifdef RTC_INT +#ifdef RTC_INT // if we have hardware pps signal we use it as precise time base #ifndef RTC_CLK // assure we know external clock freq #error "External clock cycle not defined in board hal file" @@ -65,24 +64,20 @@ int dcf77_init(void) { return 0; // failure } -// if we don't have pps signal from RTC we emulate it using ESP32 hardware timer -#else +#else // if we don't have pps signal from RTC we use ESP32 hardware timer + #define RTC_CLK (DCF77_PULSE_DURATION) // setup clock cycle ESP_LOGI(TAG, "Time base ESP32 clock"); dcfCycle = timerBegin(1, 8000, true); // set 80 MHz prescaler to 1/10000 sec timerAttachInterrupt(dcfCycle, &DCF77IRQ, true); - timerAlarmWrite(dcfCycle, 10 * RTC_CLK, true); // RTC_CLK / 1sec = 100ms + timerAlarmWrite(dcfCycle, 10 * RTC_CLK, true); // 100ms + #endif // wait until beginning of next second, then kick off first DCF pulse and // start clock signal - t = tt = now(); - do { - tt = now(); - } while (t == tt); - - DCF_Out(second(tt)); + DCF_Out(sync_clock(now())); #ifdef RTC_INT // start external clock attachInterrupt(digitalPinToInterrupt(RTC_INT), DCF77IRQ, FALLING); @@ -93,6 +88,103 @@ int dcf77_init(void) { return 1; // success } // ifdcf77_init +// called every 100msec by hardware timer to pulse out DCF signal +void DCF_Out(uint8_t startOffset) { + + static uint8_t bit = startOffset; + static uint8_t pulse = 0; +#ifdef TIME_SYNC_INTERVAL_DCF + static uint32_t nextDCFsync = millis() + TIME_SYNC_INTERVAL_DCF * 60000; +#endif + + if (!BitsPending) { + // prepare frame to send for next minute + generateTimeframe(now() + DCF77_FRAME_SIZE + 1); + // start blinking symbol on display and kick off timer + BitsPending = true; + } + + // ticker out current DCF frame + if (BitsPending) { + switch (pulse++) { + + case 0: // start of second -> start of timeframe for logic signal + if (DCFtimeframe[bit] != dcf_off) + set_DCF77_pin(dcf_low); + break; + + case 1: // 100ms after start of second -> end of timeframe for logic 0 + if (DCFtimeframe[bit] == dcf_zero) + set_DCF77_pin(dcf_high); + break; + + case 2: // 200ms after start of second -> end of timeframe for logic 1 + set_DCF77_pin(dcf_high); + break; + + case 9: // 900ms after start -> last pulse before next second starts + pulse = 0; + if (bit++ == (DCF77_FRAME_SIZE - 1)) // end of DCF77 frame (59th second) + { + bit = 0; + BitsPending = false; +// recalibrate clock after a fixed timespan, do this in 59th second +#ifdef TIME_SYNC_INTERVAL_DCF + if ((millis() >= nextDCFsync)) { + sync_clock(now()); // in second 58,90x -> waiting for second 59 + nextDCFsync = millis() + TIME_SYNC_INTERVAL_DCF * + 60000; // set up next time sync period + } +#endif + }; + break; + + }; // switch + }; // if +} // DCF_Out() + +void dcf77_loop(void *pvParameters) { + + configASSERT(((uint32_t)pvParameters) == 1); // FreeRTOS check + + TickType_t wakeTime; + + // task remains in blocked state until it is notified by isr + for (;;) { + xTaskNotifyWait( + 0x00, // don't clear any bits on entry + ULONG_MAX, // clear all bits on exit + &wakeTime, // receives moment of call from isr + portMAX_DELAY); // wait forever (missing error handling here...) + +#if (RTC_CLK == DCF77_PULSE_DURATION) + DCF_Out(0); // we don't need clock rescaling + +#else // we need clock rescaling by software timer + for (uint8_t i = 1; i <= RTC_CLK / DCF77_PULSE_DURATION; i++) { + DCF_Out(0); + vTaskDelayUntil(&wakeTime, pdMS_TO_TICKS(DCF77_PULSE_DURATION)); + } +#endif + } // for +} // dcf77_loop() + +// helper function to convert decimal to bcd digit +uint8_t dec2bcd(uint8_t dec, uint8_t startpos, uint8_t endpos, + uint8_t pArray[]) { + + uint8_t data = (dec < 10) ? dec : ((dec / 10) << 4) + (dec % 10); + uint8_t parity = 0; + + for (uint8_t n = startpos; n <= endpos; n++) { + pArray[n] = (data & 1) ? dcf_one : dcf_zero; + parity += (data & 1); + data >>= 1; + } + + return parity; +} + void generateTimeframe(time_t tt) { uint8_t ParityCount; @@ -141,93 +233,6 @@ void generateTimeframe(time_t tt) { */ } -// called every 100msec by hardware timer to pulse out DCF signal -void DCF_Out(uint8_t startOffset) { - - static uint8_t bit = startOffset; - static uint8_t pulse = 0; - - if (!BitsPending) { - // prepare frame to send for next minute - generateTimeframe(now() + 61); - // start blinking symbol on display and kick off timer - BitsPending = true; - } - - // ticker out current DCF frame - if (BitsPending) { - switch (pulse++) { - - case 0: // start of second -> start of timeframe for logic signal - if (DCFtimeframe[bit] != dcf_off) - set_DCF77_pin(dcf_low); - break; - - case 1: // 100ms after start of second -> end of timeframe for logic 0 - if (DCFtimeframe[bit] == dcf_zero) - set_DCF77_pin(dcf_high); - break; - - case 2: // 200ms after start of second -> end of timeframe for logic 1 - set_DCF77_pin(dcf_high); - break; - - case 9: // 900ms after start -> last pulse before next second starts - pulse = 0; - if (bit++ == (DCF77_FRAME_SIZE - 1)) // end of DCF77 frame (59th second) - { - bit = 0; - BitsPending = false; - }; - break; - - }; // switch - }; // if -} // DCF_Out() - -void dcf77_loop(void *pvParameters) { - - configASSERT(((uint32_t)pvParameters) == 1); // FreeRTOS check - - TickType_t wakeTime; - - // task remains in blocked state until it is notified by isr - for (;;) { - xTaskNotifyWait( - 0x00, // don't clear any bits on entry - ULONG_MAX, // clear all bits on exit - &wakeTime, // receives moment of call from isr - portMAX_DELAY); // wait forever (missing error handling here...) - -#if (!defined RTC_INT) || (RTC_CLK == DCF77_PULSE_DURATION) - DCF_Out(0); // we don't need clock rescaling - -#else // we need clock rescaling by software timer - for (uint8_t i = 1; i <= RTC_CLK / DCF77_PULSE_DURATION; i++) { - DCF_Out(0); - vTaskDelayUntil(&wakeTime, pdMS_TO_TICKS(DCF77_PULSE_DURATION)); - } // for -#endif - - } // for -} // dcf77_loop() - -// helper function to convert decimal to bcd digit -uint8_t dec2bcd(uint8_t dec, uint8_t startpos, uint8_t endpos, - uint8_t pArray[]) { - - uint8_t data = (dec < 10) ? dec : ((dec / 10) << 4) + (dec % 10); - uint8_t parity = 0; - - for (uint8_t n = startpos; n <= endpos; n++) { - pArray[n] = (data & 1) ? dcf_one : dcf_zero; - parity += (data & 1); - data >>= 1; - } - - return parity; -} - // helper function to switch GPIO line with DCF77 signal void set_DCF77_pin(dcf_pinstate state) { switch (state) { @@ -248,6 +253,20 @@ void set_DCF77_pin(dcf_pinstate state) { } // switch } // DCF77_pulse +// helper function to sync phase of DCF output signal to start of second t +uint8_t sync_clock(time_t t) { + time_t tt = t; + + // delay until start of next second + do { + tt = now(); + } while (t == tt); + + ESP_LOGI(TAG, "Sync on Sec %d", second(tt)); + + return second(tt); +} + // interrupt service routine triggered by external interrupt or internal timer void IRAM_ATTR DCF77IRQ() { xTaskNotifyFromISR(DCF77Task, xTaskGetTickCountFromISR(), eSetBits, NULL); diff --git a/src/paxcounter.conf b/src/paxcounter.conf index c796b1d8..1b6d6c3a 100644 --- a/src/paxcounter.conf +++ b/src/paxcounter.conf @@ -85,7 +85,8 @@ #define TIME_SYNC_INTERVAL_GPS 60 // sync time each .. minutes from source GPS [default = 60], comment out means off #define TIME_SYNC_INTERVAL_RTC 60 // sync time each .. minutes from RTC [default = 60], comment out means off #define TIME_WRITE_INTERVAL_RTC 60 // write time each .. minutes from GPS/LORA to RTC [default = 60], comment out means off -//#define TIME_SYNC_INTERVAL_LORA 60 // sync time each .. minutes from LORA network [default = 60], comment out means off +//#define TIME_SYNC_INTERVAL_LORA 60 // sync time each .. minutes from LORA network [default = 60], comment out means off +#define TIME_SYNC_INTERVAL_DCF 60 // sync DCF signal time each .. minutes from internal time [default = 60], comment out means off #define IF482_OFFSET 16 // IF482 serial transmit time [ms]: e.g. 9 bits * 17 bytes * 1/9600 bps = 16ms // time zone, see https://github.com/JChristensen/Timezone/blob/master/examples/WorldClock/WorldClock.ino