DigitalInfinity/ESP32-PaxCounter
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

rework dcf77

Browse Source
This commit is contained in:
cyberman54 2022-01-16 19:42:54 +01:00
parent df8d218c43
commit 83faf69c9f
2 changed files with 60 additions and 51 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
include/dcf77.h
View File

@ -12,10 +12,10 @@ enum dcf_pinstate { dcf_low, dcf_high };
enum DCF77_Pulses { dcf_Z, dcf_0, dcf_1 };
void DCF77_Pulse(time_t t, uint8_t const *DCFpulse);
uint8_t *IRAM_ATTR DCF77_Frame(time_t const tt);
uint8_t IRAM_ATTR dec2bcd(uint8_t const dec, uint8_t const startpos, uint8_t const endpos,
uint8_t *DCFpulse);
uint8_t IRAM_ATTR setParityBit(uint8_t const p);
void DCF77_Pulse(uint8_t const bit);
void DCF77_Frame(const struct tm t, uint8_t *frame);
uint8_t dec2bcd(uint8_t const dec, uint8_t const startpos, uint8_t const endpos,
uint8_t *frame);
uint8_t setParityBit(uint8_t const p);
#endif

101
src/dcf77.cpp
View File

@ -17,12 +17,9 @@ https://github.com/udoklein/dcf77
static const char TAG[] = __FILE__;
// triggered by second timepulse to ticker out DCF signal
void DCF77_Pulse(time_t t, uint8_t const *DCFpulse) {
void DCF77_Pulse(uint8_t const bit) {
TickType_t startTime = xTaskGetTickCount();
uint8_t sec = t % 60;
ESP_LOGD(TAG, "[%0.3f] DCF second: %d", _seconds(), sec);
// induce a DCF Pulse
for (uint8_t pulse = 0; pulse <= 2; pulse++) {
@ -30,12 +27,12 @@ void DCF77_Pulse(time_t t, uint8_t const *DCFpulse) {
switch (pulse) {
case 0: // start of second -> start of timeframe for logic signal
if (DCFpulse[sec] != dcf_Z)
if (bit != dcf_Z)
digitalWrite(HAS_DCF77, dcf_low);
break;
case 1: // 100ms after start of second -> end of timeframe for logic 0
if (DCFpulse[sec] == dcf_0)
if (bit == dcf_0)
digitalWrite(HAS_DCF77, dcf_high);
break;
@ -51,64 +48,78 @@ void DCF77_Pulse(time_t t, uint8_t const *DCFpulse) {
} // for
} // DCF77_Pulse()
uint8_t *IRAM_ATTR DCF77_Frame(time_t const tt) {
void DCF77_Frame(const struct tm t, uint8_t *frame) {
struct tm t = {0};
localtime_r(&tt, &t); // convert to local time
// array of dcf pulses for one minute
// secs 0..15 and 20 are never changing, thus we keep them statically to avoid
// same recalculation every minute
static uint8_t DCFpulse[61] = {dcf_0, dcf_0, dcf_0, dcf_0, dcf_0, dcf_0,
dcf_0, dcf_0, dcf_0, dcf_0, dcf_0, dcf_0,
dcf_0, dcf_0, dcf_0, dcf_0, dcf_0, dcf_0,
dcf_0, dcf_0, dcf_1};
// writes a 1 minute dcf pulse scheme for calendar time t to frame
uint8_t Parity;
// ENCODE DST CHANGE ANNOUNCEMENT (sec 16)
DCFpulse[16] = dcf_0; // not yet implemented
// START OF NEW MINUTE
frame[0] = dcf_0;
// ENCODE DAYLIGHTSAVING (secs 17..18)
// PAYLOAD -> not used here
frame[1] = dcf_0;
frame[2] = dcf_0;
frame[3] = dcf_0;
frame[4] = dcf_0;
frame[5] = dcf_0;
frame[6] = dcf_0;
frame[7] = dcf_0;
frame[8] = dcf_0;
frame[9] = dcf_0;
frame[10] = dcf_0;
frame[11] = dcf_0;
frame[12] = dcf_0;
frame[13] = dcf_0;
frame[14] = dcf_0;
frame[15] = dcf_0;
// DST CHANGE ANNOUNCEMENT
frame[16] = dcf_0; // not yet implemented
// DAYLIGHTSAVING
// "01" = MEZ / "10" = MESZ
DCFpulse[17] = (t.tm_isdst > 0) ? dcf_1 : dcf_0;
DCFpulse[18] = (t.tm_isdst > 0) ? dcf_0 : dcf_1;
frame[17] = (t.tm_isdst > 0) ? dcf_1 : dcf_0;
frame[18] = (t.tm_isdst > 0) ? dcf_0 : dcf_1;
// ENCODE MINUTE (secs 21..28)
Parity = dec2bcd(t.tm_min, 21, 27, DCFpulse);
DCFpulse[28] = setParityBit(Parity);
// LEAP SECOND
frame[19] = dcf_0; // not implemented
// ENCODE HOUR (secs 29..35)
Parity = dec2bcd(t.tm_hour, 29, 34, DCFpulse);
DCFpulse[35] = setParityBit(Parity);
// BEGIN OF TIME INFORMATION
frame[20] = dcf_1;
// ENCODE DATE (secs 36..58)
Parity = dec2bcd(t.tm_mday, 36, 41, DCFpulse);
Parity += dec2bcd((t.tm_wday == 0) ? 7 : t.tm_wday, 42, 44, DCFpulse);
Parity += dec2bcd(t.tm_mon + 1, 45, 49, DCFpulse);
Parity += dec2bcd(t.tm_year + 1900 - 2000, 50, 57, DCFpulse);
DCFpulse[58] = setParityBit(Parity);
// MINUTE (bits 21..28)
Parity = dec2bcd(t.tm_min, 21, 27, frame);
frame[28] = setParityBit(Parity);
// ENCODE MARK (sec 59)
DCFpulse[59] = dcf_Z; // !! missing code here for leap second !!
// HOUR (bits 29..35)
Parity = dec2bcd(t.tm_hour, 29, 34, frame);
frame[35] = setParityBit(Parity);
// timestamp this frame with it's minute
DCFpulse[60] = t.tm_min;
// DATE (bits 36..58)
Parity = dec2bcd(t.tm_mday, 36, 41, frame);
Parity += dec2bcd((t.tm_wday == 0) ? 7 : t.tm_wday, 42, 44, frame);
Parity += dec2bcd(t.tm_mon + 1, 45, 49, frame);
Parity += dec2bcd(t.tm_year + 1900 - 2000, 50, 57, frame);
frame[58] = setParityBit(Parity);
return DCFpulse;
// MARK (bit 59)
frame[59] = dcf_Z; // !! missing code here for leap second !!
// internal timestamp for the frame
frame[60] = t.tm_min;
} // DCF77_Frame()
// helper function to convert decimal to bcd digit
uint8_t IRAM_ATTR dec2bcd(uint8_t const dec, uint8_t const startpos,
uint8_t const endpos, uint8_t *DCFpulse) {
uint8_t dec2bcd(uint8_t const dec, uint8_t const startpos, uint8_t const endpos,
uint8_t *array) {
uint8_t data = (dec < 10) ? dec : ((dec / 10) << 4) + (dec % 10);
uint8_t parity = 0;
for (uint8_t i = startpos; i <= endpos; i++) {
DCFpulse[i] = (data & 1) ? dcf_1 : dcf_0;
array[i] = (data & 1) ? dcf_1 : dcf_0;
parity += (data & 1);
data >>= 1;
}
@ -117,8 +128,6 @@ uint8_t IRAM_ATTR dec2bcd(uint8_t const dec, uint8_t const startpos,
}
// helper function to encode parity
uint8_t IRAM_ATTR setParityBit(uint8_t const p) {
return ((p & 1) ? dcf_1 : dcf_0);
}
uint8_t setParityBit(uint8_t const p) { return ((p & 1) ? dcf_1 : dcf_0); }
#endif // HAS_DCF77