#include <ch.h> #include <hal.h> #include "led.h" #include "sleep_led.h" /* All right, we go the "software" way: timer, toggle LED in interrupt. * Based on hasu's code for AVRs. * Use LP timer on Kinetises, TIM14 on STM32F0. */ #ifndef SLEEP_LED_GPT_DRIVER # if defined(STM32F0XX) # define SLEEP_LED_GPT_DRIVER GPTD14 # endif #endif #if defined(KL2x) || defined(K20x) || defined(SLEEP_LED_GPT_DRIVER) /* common parts for timers/interrupts */ /* Breathing Sleep LED brighness(PWM On period) table * (64[steps] * 4[duration]) / 64[PWM periods/s] = 4 second breath cycle * * http://www.wolframalpha.com/input/?i=%28sin%28+x%2F64*pi%29**8+*+255%2C+x%3D0+to+63 * (0..63).each {|x| p ((sin(x/64.0*PI)**8)*255).to_i } */ static const uint8_t breathing_table[64] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 4, 6, 10, 15, 23, 32, 44, 58, 74, 93, 113, 135, 157, 179, 199, 218, 233, 245, 252, 255, 252, 245, 233, 218, 199, 179, 157, 135, 113, 93, 74, 58, 44, 32, 23, 15, 10, 6, 4, 2, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}; void sleep_led_timer_callback(void) { /* Software PWM * timer:1111 1111 1111 1111 * \_____/\/ \_______/____ count(0-255) * \ \______________ duration of step(4) * \__________________ index of step table(0-63) */ // this works for cca 65536 irqs/sec static union { uint16_t row; struct { uint8_t count : 8; uint8_t duration : 2; uint8_t index : 6; } pwm; } timer = {.row = 0}; timer.row++; // LED on if (timer.pwm.count == 0) { led_set(1 << USB_LED_CAPS_LOCK); } // LED off if (timer.pwm.count == breathing_table[timer.pwm.index]) { led_set(0); } } #endif /* common parts for known platforms */ #if defined(KL2x) || defined(K20x) /* platform selection: familiar Kinetis chips */ /* Use Low Power Timer (LPTMR) */ # define TIMER_INTERRUPT_VECTOR KINETIS_LPTMR0_IRQ_VECTOR # define RESET_COUNTER LPTMR0->CSR |= LPTMRx_CSR_TCF /* LPTMR clock options */ # define LPTMR_CLOCK_MCGIRCLK 0 /* 4MHz clock */ # define LPTMR_CLOCK_LPO 1 /* 1kHz clock */ # define LPTMR_CLOCK_ERCLK32K 2 /* external 32kHz crystal */ # define LPTMR_CLOCK_OSCERCLK 3 /* output from OSC */ /* Work around inconsistencies in Freescale naming */ # if !defined(SIM_SCGC5_LPTMR) # define SIM_SCGC5_LPTMR SIM_SCGC5_LPTIMER # endif /* interrupt handler */ OSAL_IRQ_HANDLER(TIMER_INTERRUPT_VECTOR) { OSAL_IRQ_PROLOGUE(); sleep_led_timer_callback(); /* Reset the counter */ RESET_COUNTER; OSAL_IRQ_EPILOGUE(); } /* Initialise the timer */ void sleep_led_init(void) { /* Make sure the clock to the LPTMR is enabled */ SIM->SCGC5 |= SIM_SCGC5_LPTMR; /* Reset LPTMR settings */ LPTMR0->CSR = 0; /* Set the compare value */ LPTMR0->CMR = 0; // trigger on counter value (i.e. every time) /* Set up clock source and prescaler */ /* Software PWM * ______ ______ __ * | ON |___OFF___| ON |___OFF___| .... * |<-------------->|<-------------->|<- .... * PWM period PWM period * * R interrupts/period[resolution] * F periods/second[frequency] * R * F interrupts/second */ /* === OPTION 1 === */ # if 0 // 1kHz LPO // No prescaler => 1024 irqs/sec // Note: this is too slow for a smooth breathe LPTMR0->PSR = LPTMRx_PSR_PCS(LPTMR_CLOCK_LPO)|LPTMRx_PSR_PBYP; # endif /* OPTION 1 */ /* === OPTION 2 === */ # if 1 // nMHz IRC (n=4 on KL25Z, KL26Z and K20x; n=2 or 8 on KL27Z) MCG->C2 |= MCG_C2_IRCS; // fast (4MHz) internal ref clock # if defined(KL27) // divide the 8MHz IRC by 2, to have the same MCGIRCLK speed as others MCG->MC |= MCG_MC_LIRC_DIV2_DIV2; # endif /* KL27 */ MCG->C1 |= MCG_C1_IRCLKEN; // enable internal ref clock // to work in stop mode, also MCG_C1_IREFSTEN // Divide 4MHz by 2^N (N=6) => 62500 irqs/sec => // => approx F=61, R=256, duration = 4 LPTMR0->PSR = LPTMRx_PSR_PCS(LPTMR_CLOCK_MCGIRCLK) | LPTMRx_PSR_PRESCALE(6); # endif /* OPTION 2 */ /* === OPTION 3 === */ # if 0 // OSC output (external crystal), usually 8MHz or 16MHz OSC0->CR |= OSC_CR_ERCLKEN; // enable ext ref clock // to work in stop mode, also OSC_CR_EREFSTEN // Divide by 2^N LPTMR0->PSR = LPTMRx_PSR_PCS(LPTMR_CLOCK_OSCERCLK)|LPTMRx_PSR_PRESCALE(7); # endif /* OPTION 3 */ /* === END OPTIONS === */ /* Interrupt on TCF set (compare flag) */ nvicEnableVector(LPTMR0_IRQn, 2); // vector, priority LPTMR0->CSR |= LPTMRx_CSR_TIE; } void sleep_led_enable(void) { /* Enable the timer */ LPTMR0->CSR |= LPTMRx_CSR_TEN; } void sleep_led_disable(void) { /* Disable the timer */ LPTMR0->CSR &= ~LPTMRx_CSR_TEN; } void sleep_led_toggle(void) { /* Toggle the timer */ LPTMR0->CSR ^= LPTMRx_CSR_TEN; } #elif defined(SLEEP_LED_GPT_DRIVER) static void gptTimerCallback(GPTDriver *gptp) { (void)gptp; sleep_led_timer_callback(); } static const GPTConfig gptcfg = {1000000, gptTimerCallback, 0, 0}; /* Initialise the timer */ void sleep_led_init(void) { gptStart(&SLEEP_LED_GPT_DRIVER, &gptcfg); } void sleep_led_enable(void) { gptStartContinuous(&SLEEP_LED_GPT_DRIVER, gptcfg.frequency / 0xFFFF); } void sleep_led_disable(void) { gptStopTimer(&SLEEP_LED_GPT_DRIVER); } void sleep_led_toggle(void) { (SLEEP_LED_GPT_DRIVER.state == GPT_READY) ? sleep_led_enable() : sleep_led_disable(); } #else /* platform selection: not on familiar chips */ void sleep_led_init(void) {} void sleep_led_enable(void) { led_set(1 << USB_LED_CAPS_LOCK); } void sleep_led_disable(void) { led_set(0); } void sleep_led_toggle(void) { // not implemented } #endif /* platform selection */