steven niu / WakeUp

add the implementation of LP1768 wakeup based on the old WakeUp library

Dependencies:   LPC1114_WakeInterruptIn

Fork of WakeUp by steven niu

WakeUp_LPC1768.cpp@7:542c0ca509e5, 2014-07-21 (annotated)

Committer:
steniu01
Date:
Mon Jul 21 13:45:48 2014 +0000
Revision:
7:542c0ca509e5
used to wake up after enter power mode;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
steniu01 7:542c0ca509e5 1 /**
steniu01 7:542c0ca509e5 2 Due to lack of another option for the LPC11u24 the watchdog timer is used as wakeup source.
steniu01 7:542c0ca509e5 3 Since if the reset on watchdog event bit is set, I cannot remove it again, this means if you also got watchdog code running
steniu01 7:542c0ca509e5 4 the most likely result is that it just resets your board.
steniu01 7:542c0ca509e5 5 **/
steniu01 7:542c0ca509e5 6
steniu01 7:542c0ca509e5 7
steniu01 7:542c0ca509e5 8 #ifdef TARGET_LPC1768
steniu01 7:542c0ca509e5 9
steniu01 7:542c0ca509e5 10 #include "WakeUp.h"
steniu01 7:542c0ca509e5 11
steniu01 7:542c0ca509e5 12 FunctionPointer WakeUp::callback;
steniu01 7:542c0ca509e5 13 float WakeUp::cycles_per_ms = 5.0;
steniu01 7:542c0ca509e5 14
steniu01 7:542c0ca509e5 15 void WakeUp::set_ms(uint32_t ms)
steniu01 7:542c0ca509e5 16 {
steniu01 7:542c0ca509e5 17
steniu01 7:542c0ca509e5 18 LPC_WDT->WDCLKSEL = 0x2; // Set CLK src to PCLK
steniu01 7:542c0ca509e5 19 //uint32_t clk = SystemCoreClock / 16; // WD has a fixed /4 prescaler, PCLK default is /4
steniu01 7:542c0ca509e5 20 // LPC_WDT->WDTC = ms * (float)clk/1000;
steniu01 7:542c0ca509e5 21 LPC_WDT->WDTC = (ms/4.0)*32768/1000;
steniu01 7:542c0ca509e5 22 LPC_WDT->WDMOD = 0x3; // Enabled and Reset enabled, if not reset, WDINT will not be clearred
steniu01 7:542c0ca509e5 23
steniu01 7:542c0ca509e5 24 NVIC_SetVector(WDT_IRQn, (uint32_t)WakeUp::irq_handler);
steniu01 7:542c0ca509e5 25
steniu01 7:542c0ca509e5 26 //Feeeeeed me
steniu01 7:542c0ca509e5 27 LPC_WDT->WDFEED = 0xAA;
steniu01 7:542c0ca509e5 28 LPC_WDT->WDFEED = 0x55;
steniu01 7:542c0ca509e5 29 NVIC_ClearPendingIRQ(WDT_IRQn);
steniu01 7:542c0ca509e5 30 NVIC_EnableIRQ(WDT_IRQn);
steniu01 7:542c0ca509e5 31
steniu01 7:542c0ca509e5 32 }
steniu01 7:542c0ca509e5 33
steniu01 7:542c0ca509e5 34 void WakeUp::irq_handler(void)
steniu01 7:542c0ca509e5 35 { //SCB->AIRCR |= 1<< SCB_AIRCR_SYSRESETREQ_Pos; // request a reset to get out of deepesleep
steniu01 7:542c0ca509e5 36 LPC_WDT->WDMOD = 1<<3;
steniu01 7:542c0ca509e5 37 // LPC_WDT->WDMOD &= ~(1<<2);
steniu01 7:542c0ca509e5 38 // LPC_WDT->WDMOD |= 1<<2;
steniu01 7:542c0ca509e5 39 // SCB->AIRCR |= 1<< SCB_AIRCR_SYSRESETREQ_Pos; // request a reset to get out of deepesleep
steniu01 7:542c0ca509e5 40 NVIC_DisableIRQ(WDT_IRQn);
steniu01 7:542c0ca509e5 41 callback.call();
steniu01 7:542c0ca509e5 42 }
steniu01 7:542c0ca509e5 43
steniu01 7:542c0ca509e5 44 void WakeUp::calibrate(void)
steniu01 7:542c0ca509e5 45 {
steniu01 7:542c0ca509e5 46 cycles_per_ms = 5.0;
steniu01 7:542c0ca509e5 47 set_ms(1100);
steniu01 7:542c0ca509e5 48 wait_ms(10); //Give time to sync
steniu01 7:542c0ca509e5 49 uint32_t count1 = LPC_WDT->WDTV;
steniu01 7:542c0ca509e5 50 wait_ms(100);
steniu01 7:542c0ca509e5 51 uint32_t count2 = LPC_WDT->WDTV;
steniu01 7:542c0ca509e5 52 set_ms(0);
steniu01 7:542c0ca509e5 53 count1 = count1 - count2;
steniu01 7:542c0ca509e5 54
steniu01 7:542c0ca509e5 55 cycles_per_ms = count1 / 100.0;
steniu01 7:542c0ca509e5 56 }
steniu01 7:542c0ca509e5 57
steniu01 7:542c0ca509e5 58 #endif
steniu01 7:542c0ca509e5 59