diff --git a/lib/rtc_ds1307.c b/lib/rtc_ds1307.c index e4bc6b7..b0ed66d 100644 --- a/lib/rtc_ds1307.c +++ b/lib/rtc_ds1307.c @@ -17,7 +17,7 @@ * @author King Kévin * @date 2016 * @note user RAM is not handled - * @note peripherals used: I2C @ref rtc_ds1307_i2c, GPIO @ref rtc_ds1307_square_wave + * @note peripherals used: I2C @ref rtc_ds1307_i2c, GPIO & timer @ref rtc_ds1307_square_wave_timer */ /* standard libraries */ @@ -31,34 +31,23 @@ #include // I2C library #include // interrupt handler #include // Cortex M3 utilities +#include // timer utilities #include "global.h" // global utilities #include "rtc_ds1307.h" // RTC header and definitions -/** @defgroup rtc_ds1307_i2c I2C peripheral used to communication with the DS1307 RTC IC - * @{ - */ -/** I2C peripheral */ -#define I2C I2C1 /**< I2C peripheral */ -#define I2C_RCC RCC_I2C1 /**< I2C peripheral clock */ -#define I2C_PORT GPIOB /**< I2C peripheral port */ -#define I2C_PIN_SDA GPIO_I2C1_SDA /**< I2C peripheral data pin (PB7) */ -#define I2C_PIN_SCL GPIO_I2C1_SCL /**< I2C peripheral clock pin (PB6) */ -/** @} */ -#define I2C_ADDR 0x68 /**< DS1307 I2C address (fixed to 0b1101000) */ - -#if defined(SQUARE_WAVE_EXTI) && defined(SQUARE_WAVE_IRQ) && defined(SQUARE_WAVE_ISR) && defined(SQUARE_WAVE_HANDLING) && SQUARE_WAVE_HANDLING -volatile bool square_wave_flag = false; +#if defined(SQUARE_WAVE_TICKS) +volatile bool rtc_tick_flag = false; #endif void rtc_setup(void) { - /* enable peripheral */ + // enable peripheral rcc_periph_clock_enable(RCC_AFIO); // enable clock for alternate function rcc_periph_clock_enable(I2C_RCC); // enable clock for I2C peripheral gpio_set_mode(I2C_PORT, GPIO_MODE_OUTPUT_10_MHZ, GPIO_CNF_OUTPUT_ALTFN_OPENDRAIN, I2C_PIN_SDA | I2C_PIN_SCL); // setup I2C pin - /* configure I2C peripheral (see RM008 26.3.3, I2C master) */ + // configure I2C peripheral (see RM008 26.3.3, I2C master) i2c_reset(I2C); // reset configuration i2c_peripheral_disable(I2C); // I2C needs to be disable to be configured i2c_set_clock_frequency(I2C, rcc_apb1_frequency/1E6); // configure the peripheral clock to the APB1 freq (where it is connected to) @@ -67,20 +56,28 @@ void rtc_setup(void) i2c_set_trise(I2C, rcc_apb1_frequency/1E6); // max rise time for 100 kHz is 1000 ns (~1 MHz) i2c_peripheral_enable(I2C); // enable I2C after configuration completed - /* setup square wave interrupt input */ -#if defined(SQUARE_WAVE_RCC) && defined(SQUARE_WAVE_PORT) && defined(SQUARE_WAVE_PIN) - rcc_periph_clock_enable(SQUARE_WAVE_RCC); // enable GPIO peripheral - gpio_set_mode(SQUARE_WAVE_PORT, GPIO_MODE_INPUT, GPIO_CNF_INPUT_PULL_UPDOWN, SQUARE_WAVE_PIN); // set pin to input with pull up - gpio_set(SQUARE_WAVE_PORT, SQUARE_WAVE_PIN); // pull up since the square wave output is open drain -#if defined(SQUARE_WAVE_EXTI) && defined(SQUARE_WAVE_IRQ) && defined(SQUARE_WAVE_ISR) - rcc_periph_clock_enable(RCC_AFIO); // enable alternate function clock for external interrupt - exti_select_source(SQUARE_WAVE_EXTI, SQUARE_WAVE_PORT); // mask external interrupt of this pin only for this port - exti_set_trigger(SQUARE_WAVE_EXTI, EXTI_TRIGGER_FALLING); // trigger on falling - exti_enable_request(SQUARE_WAVE_EXTI); // enable external interrupt - nvic_enable_irq(SQUARE_WAVE_IRQ); // enable interrupt +#if defined(SQUARE_WAVE_TICKS) + // setup timer to generate tick from square wave output + rcc_periph_clock_enable(SQUARE_WAVE_GPIO_RCC); // enable clock for GPIO peripheral + gpio_set_mode(SQUARE_WAVE_GPIO_PORT, GPIO_MODE_INPUT, GPIO_CNF_INPUT_PULL_UPDOWN, SQUARE_WAVE_GPIO_PIN); // set pin as input + gpio_set(SQUARE_WAVE_GPIO_PORT, SQUARE_WAVE_GPIO_PIN); // enable pull-up + rcc_periph_clock_enable(SQUARE_WAVE_TIMER_RCC); // enable clock for timer peripheral + timer_reset(SQUARE_WAVE_TIMER); // reset timer state + timer_ic_set_input(SQUARE_WAVE_TIMER, SQUARE_WAVE_TIMER_IC, SQUARE_WAVE_TIMER_IN); // configure channel as input capture + timer_ic_set_filter(SQUARE_WAVE_TIMER, SQUARE_WAVE_TIMER_IC, TIM_IC_OFF); // use no input capture filter + timer_ic_set_polarity(SQUARE_WAVE_TIMER, SQUARE_WAVE_TIMER_IC, TIM_IC_FALLING); //capture on falling edge + timer_slave_set_trigger(SQUARE_WAVE_TIMER, SQUARE_WAVE_TIMER_TS); // select trigger + timer_slave_set_mode(SQUARE_WAVE_TIMER, TIM_SMCR_SMS_ECM1); // select external clock more 1 as input + timer_ic_enable(SQUARE_WAVE_TIMER, SQUARE_WAVE_TIMER_IC); // enable input capture + timer_set_mode(SQUARE_WAVE_TIMER, TIM_CR1_CKD_CK_INT, TIM_CR1_CMS_EDGE, TIM_CR1_DIR_UP); // set timer mode, use undivided timer clock, edge alignment (simple count), and count up + timer_set_prescaler(SQUARE_WAVE_TIMER, 0); // no need to prescale + timer_set_period(SQUARE_WAVE_TIMER, SQUARE_WAVE_TICKS-1); // set the tick period + timer_enable_irq(SQUARE_WAVE_TIMER, TIM_DIER_UIE); // enable interrupt for timer + nvic_enable_irq(SQUARE_WAVE_TIMER_IRQ); // allow interrupt for timer + rtc_tick_flag = false; // reset RTC tick flag + timer_enable_counter(SQUARE_WAVE_TIMER); // enable timer to count ticks + rtc_write_square_wave(SQUARE_WAVE_FREQUENCY); // set square wave output frequency #endif -#endif - } /** @brief read memory from RTC IC @@ -447,12 +444,14 @@ bool rtc_write_time(uint8_t seconds, uint8_t minutes, uint8_t hours, uint8_t day return rtc_write_memory(0, data, LENGTH(data)); // write time values on RTC } -#if defined(SQUARE_WAVE_EXTI) && defined(SQUARE_WAVE_IRQ) && defined(SQUARE_WAVE_ISR) && defined(SQUARE_WAVE_HANDLING) && SQUARE_WAVE_HANDLING -/** @brief square wave input interrupt */ -void SQUARE_WAVE_ISR(void) +#if defined(SQUARE_WAVE_TICKS) +/** @brief timer interrupt service routine called when number of ticks have been received */ +void SQUARE_WAVE_TIMER_ISR(void) { - exti_reset_request(SQUARE_WAVE_EXTI); // reset interrupt - square_wave_flag = true; // update flag + if (timer_get_flag(SQUARE_WAVE_TIMER, TIM_SR_UIF)) { // overflow even happened + timer_clear_flag(SQUARE_WAVE_TIMER, TIM_SR_UIF); // clear flag + rtc_tick_flag = true; // update flag + } } #endif diff --git a/lib/rtc_ds1307.h b/lib/rtc_ds1307.h index 02dff6a..7abe523 100644 --- a/lib/rtc_ds1307.h +++ b/lib/rtc_ds1307.h @@ -17,24 +17,42 @@ * @author King Kévin * @date 2016 * @note user RAM is not handled - * @note peripherals used: I2C @ref rtc_ds1307_i2c, GPIO @ref rtc_ds1307_square_wave + * @note peripherals used: I2C @ref rtc_ds1307_i2c, GPIO & timer @ref rtc_ds1307_square_wave_timer */ #pragma once -/** @defgroup rtc_ds1307_square_wave connect Maxim DS1307 square wave output (on PB10) +/** @defgroup rtc_ds1307_i2c I2C peripheral used to communication with the DS1307 RTC IC * @{ */ -#define SQUARE_WAVE_RCC RCC_GPIOB /**< GPIO peripheral clock (port B) */ -#define SQUARE_WAVE_PORT GPIOB /**< GPIO port (port B) */ -#define SQUARE_WAVE_PIN GPIO10 /**< GPIO pin (pin PA10) */ -#define SQUARE_WAVE_EXTI EXTI10 /**< GPIO external interrupt (exti 10 for pin 12) */ -//#define SQUARE_WAVE_IRQ NVIC_EXTI15_10_IRQ /**< GPIO line interrupt (interrupt for line 15 to 10 for pin 10) */ -//#define SQUARE_WAVE_ISR exti15_10_isr /**< GPIO line interrupt service routine (isr for line 15 to 10 for pin 10) */ -//#define SQUARE_WAVE_HANDLING true /**< to to have the library handle the square wave interrupt (setting square_wave_flag) */ +/** I2C peripheral */ +#define I2C I2C1 /**< I2C peripheral */ +#define I2C_RCC RCC_I2C1 /**< I2C peripheral clock */ +#define I2C_PORT GPIOB /**< I2C peripheral port */ +#define I2C_PIN_SDA GPIO_I2C1_SDA /**< I2C peripheral data pin (PB7) */ +#define I2C_PIN_SCL GPIO_I2C1_SCL /**< I2C peripheral clock pin (PB6) */ +#define I2C_ADDR 0x68 /**< DS1307 I2C address (fixed to 0b1101000) */ /** @} */ -#if defined(SQUARE_WAVE_EXTI) && defined(SQUARE_WAVE_IRQ) && defined(SQUARE_WAVE_ISR) && defined(SQUARE_WAVE_HANDLING) && SQUARE_WAVE_HANDLING -extern volatile bool square_wave_flag; /**< set on square wave output */ +/** @defgroup rtc_ds1307_square_wave_timer timer peripheral used to count timer based on RTC IC square wave output + * @note comment out SQUARE_WAVE_TICS to not disable feature + * @{ + */ +#define SQUARE_WAVE_TICKS SQUARE_WAVE_FREQUENCY/256 /**< number of square wave tics before setting rtc_tic_flag */ +#define SQUARE_WAVE_FREQUENCY 4096 /**< square wave output frequency from the RTC IC */ +#define SQUARE_WAVE_TIMER TIM2 /**< timer peripheral */ +#define SQUARE_WAVE_TIMER_RCC RCC_TIM2 /**< timer peripheral clock */ +#define SQUARE_WAVE_TIMER_IC TIM_IC1 /**< input capture channel (for TIM2_CH1) */ +#define SQUARE_WAVE_TIMER_IN TIM_IC_IN_TI1 /**< input capture input source (TIM2_CH1 becomes TI1, then TI1F, then TI1FP1) */ +#define SQUARE_WAVE_TIMER_TS TIM_SMCR_TS_IT1FP1 /**< input capture trigger (actually TI1FP1) */ +#define SQUARE_WAVE_TIMER_IRQ NVIC_TIM2_IRQ /**< timer interrupt */ +#define SQUARE_WAVE_TIMER_ISR tim2_isr /**< timer interrupt service routine */ +#define SQUARE_WAVE_GPIO_RCC RCC_GPIOA /**< timer port peripheral clock (TIM2_CH1 on PA0)*/ +#define SQUARE_WAVE_GPIO_PORT GPIOA /**< timer port (TIM2_CH1 on PA0) */ +#define SQUARE_WAVE_GPIO_PIN GPIO_TIM2_CH1_ETR /**< timer pin input, connect to RTC IC square wave output (TIM2_CH1 on PA0) */ +/** @} */ + +#if defined(SQUARE_WAVE_TICKS) +extern volatile bool rtc_tick_flag; /**< set on SQUARE_WAVE_TICS square wave tics */ #endif /** @brief setup communication with RTC IC