gpsread.cpp: comments edited

This commit is contained in:
Klaus K Wilting 2020-09-29 17:27:52 +02:00
parent c1c7ae4de8
commit 73104cafeb

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@ -6,8 +6,11 @@
// Local logging tag // Local logging tag
static const char TAG[] = __FILE__; static const char TAG[] = __FILE__;
// we use NMEA $GPZDA sentence field 1 for time synchronization // we use NMEA ZDA sentence field 1 for time synchronization
// $GPZDA gives time for preceding pps pulse, but does not has a constant offset // ZDA gives time for preceding pps pulse
// downsight is that it does not have a constant offset
// thus precision is only +/- 1 second
TinyGPSPlus gps; TinyGPSPlus gps;
TinyGPSCustom gpstime(gps, "GPZDA", 1); // field 1 = UTC time TinyGPSCustom gpstime(gps, "GPZDA", 1); // field 1 = UTC time
static const String ZDA_Request = "$EIGPQ,ZDA*39\r\n"; static const String ZDA_Request = "$EIGPQ,ZDA*39\r\n";
@ -95,7 +98,7 @@ time_t get_gpstime(uint16_t *msec) {
time_t time_sec = 0; time_t time_sec = 0;
// poll NMEA $GPZDA sentence // poll NMEA ZDA sentence
#ifdef GPS_SERIAL #ifdef GPS_SERIAL
GPS_Serial.print(ZDA_Request); GPS_Serial.print(ZDA_Request);
// wait for gps NMEA answer // wait for gps NMEA answer