Andrew Boyson / clock

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Dependents:   oldheating gps motorhome heating

clock-ntp.c@17:927fc1eceb9d, 2018-01-11 (annotated)

Committer:
andrewboyson
Date:
Thu Jan 11 17:39:36 2018 +0000
Revision:
17:927fc1eceb9d
Parent:
clock-ntp.cpp@11:6efacb859c93
Child:
18:207dd1474cd9
Removed dependence on Mbed OS

Who changed what in which revision?

UserRevisionLine numberNew contents of line
andrewboyson 17:927fc1eceb9d 1 #include <stdint.h>
andrewboyson 17:927fc1eceb9d 2
andrewboyson 10:19ed22b94c99 3
andrewboyson 11:6efacb859c93 4 #define SECONDS_BETWEEN_1900_AND_1970 2208988800ULL
andrewboyson 11:6efacb859c93 5 #define ONE_BILLION 1000000000LL
andrewboyson 10:19ed22b94c99 6
andrewboyson 11:6efacb859c93 7 #define ERA_BASE_LOW 1 //Adjust this from 0 to 1 between 1968 and 2036; 1 to 2 between 2104 and 2168
andrewboyson 11:6efacb859c93 8 #define ERA_BASE_HGH 0 //Adjust this from 0 to 1 between 2036 and 2104; 1 to 2 between 2172 and 2240
andrewboyson 11:6efacb859c93 9
andrewboyson 17:927fc1eceb9d 10 #define ERA_LOW_SECS ERA_BASE_LOW * (1LL << 32)
andrewboyson 17:927fc1eceb9d 11 #define ERA_HGH_SECS ERA_BASE_HGH * (1LL << 32)
andrewboyson 17:927fc1eceb9d 12 #define ERA_LOW_NS ERA_LOW_SECS * ONE_BILLION
andrewboyson 17:927fc1eceb9d 13 #define ERA_HGH_NS ERA_HGH_SECS * ONE_BILLION
andrewboyson 10:19ed22b94c99 14
andrewboyson 10:19ed22b94c99 15 uint64_t ClockNtpTimeStampFromNs(int64_t ns)
andrewboyson 10:19ed22b94c99 16 {
andrewboyson 10:19ed22b94c99 17 uint64_t timestamp = ns << 2;
andrewboyson 10:19ed22b94c99 18 timestamp /= 1000; timestamp <<= 10;
andrewboyson 10:19ed22b94c99 19 timestamp /= 1000; timestamp <<= 10;
andrewboyson 10:19ed22b94c99 20 timestamp /= 1000; timestamp <<= 10;
andrewboyson 10:19ed22b94c99 21
andrewboyson 11:6efacb859c93 22 timestamp += SECONDS_BETWEEN_1900_AND_1970 << 32; //This should just wrap around the unsigned timestamp removing the unwanted era.
andrewboyson 10:19ed22b94c99 23
andrewboyson 10:19ed22b94c99 24 return timestamp;
andrewboyson 10:19ed22b94c99 25 }
andrewboyson 10:19ed22b94c99 26 int64_t ClockNtpTimeStampToNs(uint64_t timestamp)
andrewboyson 10:19ed22b94c99 27 {
andrewboyson 17:927fc1eceb9d 28 int isHigh = (timestamp & (1ULL << 63)) != 0;
andrewboyson 11:6efacb859c93 29
andrewboyson 11:6efacb859c93 30 int64_t ns = timestamp - (SECONDS_BETWEEN_1900_AND_1970 << 32);
andrewboyson 10:19ed22b94c99 31 ns >>= 10; ns *= 1000;
andrewboyson 10:19ed22b94c99 32 ns >>= 10; ns *= 1000;
andrewboyson 10:19ed22b94c99 33 ns >>= 10; ns *= 1000;
andrewboyson 10:19ed22b94c99 34
andrewboyson 10:19ed22b94c99 35 ns >>= 2;
andrewboyson 10:19ed22b94c99 36
andrewboyson 11:6efacb859c93 37 //Correct for era
andrewboyson 11:6efacb859c93 38 if (isHigh) ns += ERA_HGH_NS;
andrewboyson 11:6efacb859c93 39 else ns += ERA_LOW_NS;
andrewboyson 11:6efacb859c93 40
andrewboyson 10:19ed22b94c99 41 return ns;
andrewboyson 10:19ed22b94c99 42 }
andrewboyson 10:19ed22b94c99 43