Andrew Boyson / clock

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Dependents:   oldheating gps motorhome heating

clock.txt@40:53666b1a5848, 2018-12-04 (annotated)

Committer:
andrewboyson
Date:
Tue Dec 04 12:26:27 2018 +0000
Revision:
40:53666b1a5848
Parent:
39:5b594b1b6a0a 
Renamed timer to hrtimer; added clktimer to handle utc based times.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
andrewboyson 35:ba9f575aa3c6 1 The clock library provides a number of separate functions:
andrewboyson 40:53666b1a5848 2 * "hrtimer" An unsigned 32bit high resolution timer which wraps around every 44 seconds from which all the time is derived.
andrewboyson 40:53666b1a5848 3 * "mstimer" An unsigned 32bit low resolution timer which wraps around every 49 days
andrewboyson 40:53666b1a5848 4 * "clktimer" A signed 64bit utc linked timer which doesn't wrap (or not until 2242 when clock time breaks)
andrewboyson 40:53666b1a5848 5 * "scan" Calculates the max, min and average scan times.
andrewboyson 40:53666b1a5848 6 * "rtc" A real time clock to provide backup
andrewboyson 40:53666b1a5848 7 * "tm" Routines to manipulate struct tm local and utc times
andrewboyson 40:53666b1a5848 8 * "clock" A clock which is synchronised to an external source
andrewboyson 35:ba9f575aa3c6 9
andrewboyson 35:ba9f575aa3c6 10 High resolution timer
andrewboyson 35:ba9f575aa3c6 11 =====================
andrewboyson 40:53666b1a5848 12 hrtimer.c uses TIM0 as a 32bit timer which counts at the cpu frequency 96MHz and rolls over after about 44s.
andrewboyson 35:ba9f575aa3c6 13 It has an init routine called from ClockInit to start it, thereafter it free runs.
andrewboyson 35:ba9f575aa3c6 14 No dependancies.
andrewboyson 35:ba9f575aa3c6 15
andrewboyson 40:53666b1a5848 16 Millisecond timer
andrewboyson 40:53666b1a5848 17 =================
andrewboyson 38:25b2a3c494aa 18 mstimer.c uses the high resolution timer to count the number of ms since power up. Its unsigned 32bit count rolls over after about 49 days.
andrewboyson 35:ba9f575aa3c6 19 It has a main routine called from ClockMain.
andrewboyson 35:ba9f575aa3c6 20 Depends on timer.
andrewboyson 35:ba9f575aa3c6 21
andrewboyson 40:53666b1a5848 22 Clock timer
andrewboyson 40:53666b1a5848 23 ===========
andrewboyson 40:53666b1a5848 24 clktimer.h uses the signed 64 bit clock time.
andrewboyson 40:53666b1a5848 25 Depends on clock and hence hrtimer.
andrewboyson 40:53666b1a5848 26
andrewboyson 36:6a8a8e1951d4 27 Scan times
andrewboyson 36:6a8a8e1951d4 28 ==========
andrewboyson 36:6a8a8e1951d4 29 scan.c uses the high resolution timer to calculate the max, min and average scan times.
andrewboyson 36:6a8a8e1951d4 30 It has a main routine called from ClockMain.
andrewboyson 40:53666b1a5848 31 Depends on hrtimer.
andrewboyson 36:6a8a8e1951d4 32
andrewboyson 35:ba9f575aa3c6 33 Real time clock
andrewboyson 35:ba9f575aa3c6 34 ===============
andrewboyson 35:ba9f575aa3c6 35 rtc.c contains routines to save and restore the time in the battery backed real time clock.
andrewboyson 35:ba9f575aa3c6 36 It speaks struct tm.
andrewboyson 35:ba9f575aa3c6 37 No dependancies.
andrewboyson 35:ba9f575aa3c6 38
andrewboyson 35:ba9f575aa3c6 39 Local and UTC manipulation
andrewboyson 35:ba9f575aa3c6 40 ==========================
andrewboyson 38:25b2a3c494aa 41 tm.c contains a number of functions for manipulating 64 bit seconds since 1970 and struct tm times.
andrewboyson 38:25b2a3c494aa 42 It contains nothing for clock time or the high resolution count.
andrewboyson 38:25b2a3c494aa 43 time_t is used in the expectation that it will become 64 bit before 2038; if not then replace time_t with int64_t and replace TimeT with Secs1970
andrewboyson 35:ba9f575aa3c6 44 No dependancies.
andrewboyson 35:ba9f575aa3c6 45
andrewboyson 31:f6ff7fdb9c67 46 Clock
andrewboyson 31:f6ff7fdb9c67 47 =====
andrewboyson 31:f6ff7fdb9c67 48 clock.c contains
andrewboyson 31:f6ff7fdb9c67 49 * settings
andrewboyson 31:f6ff7fdb9c67 50 * functions to save and restore the time to the RTC.
andrewboyson 35:ba9f575aa3c6 51 Depends on timer, rtc and tm.
andrewboyson 10:19ed22b94c99 52
andrewboyson 33:b9e3c06e7dab 53 clkstate.c contains state (ppb and slew) and settings (changes to the defaulsts are set up in the main program)
andrewboyson 33:b9e3c06e7dab 54 PPB is stored in GPREG0 whenever it is set and retrieved during initialisation.
andrewboyson 33:b9e3c06e7dab 55
andrewboyson 33:b9e3c06e7dab 56 clktime.c increments by 1 each second via clock.c from timer.c. It increments the clock time using the ppb and slew (set by sync.c).
andrewboyson 33:b9e3c06e7dab 57 When the clock time is requested it uses its count and a proportion of the elapsed second from the high resolution timer to calculate the exact time.
andrewboyson 33:b9e3c06e7dab 58 See time-formats.text for the clock time format.
andrewboyson 31:f6ff7fdb9c67 59
andrewboyson 35:ba9f575aa3c6 60 clksync.c takes external time from either:
andrewboyson 31:f6ff7fdb9c67 61 * a long term source such as NTP
andrewboyson 31:f6ff7fdb9c67 62 * a pulse per second (PPS)
andrewboyson 33:b9e3c06e7dab 63 It adjusts the ppb and slew to synchronise the external source and the clock time.
andrewboyson 23:07b19cd5f6d0 64
andrewboyson 35:ba9f575aa3c6 65 clkntp.c converts clock time to NTP time and vice versa.
andrewboyson 31:f6ff7fdb9c67 66
andrewboyson 38:25b2a3c494aa 67 clktm.c converts clock time to struct tm and vice versa
andrewboyson 38:25b2a3c494aa 68