Sebastien Luzy / Mbed OS Code_STM32_projet_gestion_de_commande_en_ligne

Code projet_gestion_de_commande_en_ligne

Dependencies:   TS_DISCO_F746NG LCD_DISCO_F746NG BSP_DISCO_F746NG BUTTON_GROUP

Clock.cpp@0:735dae6ecacf, 2020-06-18 (annotated)

Committer:
darkseb
Date:
Thu Jun 18 14:45:26 2020 +0000
Revision:
0:735dae6ecacf
test

Who changed what in which revision?

UserRevisionLine numberNew contents of line
darkseb 0:735dae6ecacf 1 #include <mbed.h>
darkseb 0:735dae6ecacf 2
darkseb 0:735dae6ecacf 3 // The us ticker is a wrapping uint32_t. We insert interrupts at
darkseb 0:735dae6ecacf 4 // 0, 0x40000000, 0x8000000, and 0xC0000000, rather than just 0 or just 0xFFFFFFFF because there is
darkseb 0:735dae6ecacf 5 // code that calls interrupts that are "very soon" immediately and we don't
darkseb 0:735dae6ecacf 6 // want that. Also because if we only use 0 and 0x80000000 then there is a chance it would
darkseb 0:735dae6ecacf 7 // be considered to be in the past and executed immediately.
darkseb 0:735dae6ecacf 8
darkseb 0:735dae6ecacf 9 class ExtendedClock : public TimerEvent
darkseb 0:735dae6ecacf 10 {
darkseb 0:735dae6ecacf 11 public:
darkseb 0:735dae6ecacf 12 ExtendedClock()
darkseb 0:735dae6ecacf 13 {
darkseb 0:735dae6ecacf 14 // This also starts the us ticker.
darkseb 0:735dae6ecacf 15 insert(0x40000000);
darkseb 0:735dae6ecacf 16 }
darkseb 0:735dae6ecacf 17
darkseb 0:735dae6ecacf 18 float read()
darkseb 0:735dae6ecacf 19 {
darkseb 0:735dae6ecacf 20 return read_us() / 1000000.0f;
darkseb 0:735dae6ecacf 21 }
darkseb 0:735dae6ecacf 22
darkseb 0:735dae6ecacf 23 uint64_t read_ms()
darkseb 0:735dae6ecacf 24 {
darkseb 0:735dae6ecacf 25 return read_us() / 1000;
darkseb 0:735dae6ecacf 26 }
darkseb 0:735dae6ecacf 27
darkseb 0:735dae6ecacf 28 uint64_t read_us()
darkseb 0:735dae6ecacf 29 {
darkseb 0:735dae6ecacf 30 return mTriggers * 0x40000000ull + (ticker_read(_ticker_data) & 0x3FFFFFFF);
darkseb 0:735dae6ecacf 31 }
darkseb 0:735dae6ecacf 32
darkseb 0:735dae6ecacf 33 private:
darkseb 0:735dae6ecacf 34 void handler() override
darkseb 0:735dae6ecacf 35 {
darkseb 0:735dae6ecacf 36 ++mTriggers;
darkseb 0:735dae6ecacf 37 // If this is the first time we've been called (at 0x4...)
darkseb 0:735dae6ecacf 38 // then mTriggers now equals 1 and we want to insert at 0x80000000.
darkseb 0:735dae6ecacf 39 insert((mTriggers+1) * 0x40000000);
darkseb 0:735dae6ecacf 40 }
darkseb 0:735dae6ecacf 41
darkseb 0:735dae6ecacf 42 // The number of times the us_ticker has rolled over.
darkseb 0:735dae6ecacf 43 uint32_t mTriggers = 0;
darkseb 0:735dae6ecacf 44 };
darkseb 0:735dae6ecacf 45
darkseb 0:735dae6ecacf 46 static ExtendedClock _GlobalClock;
darkseb 0:735dae6ecacf 47
darkseb 0:735dae6ecacf 48 // Return the number of seconds since boot.
darkseb 0:735dae6ecacf 49 float clock_s()
darkseb 0:735dae6ecacf 50 {
darkseb 0:735dae6ecacf 51 return _GlobalClock.read();
darkseb 0:735dae6ecacf 52 }
darkseb 0:735dae6ecacf 53
darkseb 0:735dae6ecacf 54 // Return the number of milliseconds since boot.
darkseb 0:735dae6ecacf 55 uint64_t clock_ms()
darkseb 0:735dae6ecacf 56 {
darkseb 0:735dae6ecacf 57 return _GlobalClock.read_ms();
darkseb 0:735dae6ecacf 58 }
darkseb 0:735dae6ecacf 59
darkseb 0:735dae6ecacf 60 // Return the number of microseconds since boot.
darkseb 0:735dae6ecacf 61 uint64_t clock_us()
darkseb 0:735dae6ecacf 62 {
darkseb 0:735dae6ecacf 63 return _GlobalClock.read_us();
darkseb 0:735dae6ecacf 64 }