#include #include #include #include "libopencm3/stm32/f0/adc.h" #include "pinout.h" #include "measurement.h" #include "flash_config.h" #define ADC_NUM_CHANNELS 6 static volatile int16_t adc_values[ADC_NUM_CHANNELS]; static fxp_t calibration_factors[ADC_NUM_CHANNELS-1]; // all except temperature; filled in measurement_init() fxp_t avg_alpha_i_solar; fxp_t avg_alpha_i_load; fxp_t avg_alpha_u_bat; fxp_t avg_alpha_u_sw; fxp_t avg_alpha_u_solar; fxp_t avg_alpha_temp; fxp_t avg_alpha_i_solar_inv; fxp_t avg_alpha_i_load_inv; fxp_t avg_alpha_u_bat_inv; fxp_t avg_alpha_u_sw_inv; fxp_t avg_alpha_u_solar_inv; fxp_t avg_alpha_temp_inv; /* Temperature sensor calibration value address */ #define TEMP110_CAL_ADDR ((uint16_t*) ((uint32_t) 0x1FFFF7C2)) #define TEMP30_CAL_ADDR ((uint16_t*) ((uint32_t) 0x1FFFF7B8)) #define VDD_CALIB ((int32_t) (330)) /* calibration voltage = 3,30V - DO NOT CHANGE */ #define VDD_APPLI ((int32_t) (330)) /* actual supply voltage */ /* function for temperature conversion */ static fxp_t calc_temperature(uint16_t adc_val) { int32_t temperature_raw = ((int32_t)adc_val * VDD_APPLI / VDD_CALIB) - (int32_t)(*TEMP30_CAL_ADDR); fxp_t temperature = FXP_FROM_INT(temperature_raw); fxp_t scale_dividend = FXP_FROM_INT(110 - 30); fxp_t scale_divisor = FXP_FROM_INT((int32_t)(*TEMP110_CAL_ADDR - *TEMP30_CAL_ADDR)); fxp_t scale = fxp_div(scale_dividend, scale_divisor); return fxp_add(fxp_mult(temperature, scale), FXP_FROM_INT(30)); } static fxp_t adc_val_to_pin_voltage(uint16_t adc_val) { return fxp_div( fxp_mult(FXP_FROM_INT((int32_t)adc_val), fxp_div(FXP_FROM_INT(33), FXP_FROM_INT(10))), FXP_FROM_INT(4096)); } static fxp_t convert_voltage_divider(uint16_t adc_val, fxp_t r1, fxp_t r2, fxp_t cal) { fxp_t pin_voltage = adc_val_to_pin_voltage(adc_val); fxp_t meas_voltage = fxp_mult(pin_voltage, fxp_div(fxp_add(r1, r2), r2)); return fxp_mult(meas_voltage, cal); } static fxp_t convert_ina139(uint16_t adc_val, fxp_t rshunt, fxp_t vgain, fxp_t cal) { fxp_t pin_voltage = adc_val_to_pin_voltage(adc_val); fxp_t shunt_voltage = fxp_div(pin_voltage, vgain); fxp_t current = fxp_div(shunt_voltage, rshunt); return fxp_mult(current, cal); } void measurement_init(void) { uint8_t channels[ADC_NUM_CHANNELS] = { ANALOG_INPUT_U_BAT, // U_Bat ANALOG_INPUT_U_SOLAR, // U_Solar ANALOG_INPUT_U_SW, // U_SW ANALOG_INPUT_I_SOLAR, // I_Solar ANALOG_INPUT_I_LOAD, // I_Load ADC_CHANNEL_TEMP // Temperature sensor }; // Convert calibration factors to fixed-point numbers for direct use calibration_factors[ANALOG_INPUT_U_BAT] = fxp_div(FXP_FROM_INT(FLASH_CONFIG_CAL_FACTOR_U_BAT), FXP_FROM_INT(1000)); calibration_factors[ANALOG_INPUT_U_SOLAR] = fxp_div(FXP_FROM_INT(FLASH_CONFIG_CAL_FACTOR_U_SOLAR), FXP_FROM_INT(1000)); calibration_factors[ANALOG_INPUT_U_SW] = fxp_div(FXP_FROM_INT(FLASH_CONFIG_CAL_FACTOR_U_SW), FXP_FROM_INT(1000)); calibration_factors[ANALOG_INPUT_I_SOLAR] = fxp_div(FXP_FROM_INT(FLASH_CONFIG_CAL_FACTOR_I_SOLAR), FXP_FROM_INT(1000)); calibration_factors[ANALOG_INPUT_I_LOAD] = fxp_div(FXP_FROM_INT(FLASH_CONFIG_CAL_FACTOR_I_LOAD), FXP_FROM_INT(1000)); // Convert and precalculate coefficients for exponential averaging avg_alpha_i_solar = fxp_div(FXP_FROM_INT(FLASH_CONFIG_AVG_ALPHA_I_SOLAR), FXP_FROM_INT(1000)); avg_alpha_i_load = fxp_div(FXP_FROM_INT(FLASH_CONFIG_AVG_ALPHA_I_LOAD), FXP_FROM_INT(1000)); avg_alpha_u_bat = fxp_div(FXP_FROM_INT(FLASH_CONFIG_AVG_ALPHA_U_BAT), FXP_FROM_INT(1000)); avg_alpha_u_sw = fxp_div(FXP_FROM_INT(FLASH_CONFIG_AVG_ALPHA_U_SW), FXP_FROM_INT(1000)); avg_alpha_u_solar = fxp_div(FXP_FROM_INT(FLASH_CONFIG_AVG_ALPHA_U_SOLAR), FXP_FROM_INT(1000)); avg_alpha_temp = fxp_div(FXP_FROM_INT(FLASH_CONFIG_AVG_ALPHA_TEMP), FXP_FROM_INT(1000)); // Inverse (1 - alpha) exponential averaging coefficients avg_alpha_i_solar_inv = fxp_sub(FXP_FROM_INT(1), avg_alpha_i_solar); avg_alpha_i_load_inv = fxp_sub(FXP_FROM_INT(1), avg_alpha_i_load); avg_alpha_u_bat_inv = fxp_sub(FXP_FROM_INT(1), avg_alpha_u_bat); avg_alpha_u_sw_inv = fxp_sub(FXP_FROM_INT(1), avg_alpha_u_sw); avg_alpha_u_solar_inv = fxp_sub(FXP_FROM_INT(1), avg_alpha_u_solar); avg_alpha_temp_inv = fxp_sub(FXP_FROM_INT(1), avg_alpha_temp); // Prepare the ADC adc_power_off(ADC1); // enable the temperature sensor adc_enable_temperature_sensor(); // configure ADC //adc_enable_scan_mode(ADC1); adc_set_clk_source(ADC1, ADC_CLKSOURCE_PCLK_DIV4); // -> 12 MHz @ 48 MHz ABP adc_set_single_conversion_mode(ADC1); adc_set_resolution(ADC1, ADC_RESOLUTION_12BIT); adc_set_sample_time_on_all_channels(ADC1, ADC_SMPR_SMP_239DOT5); adc_disable_external_trigger_regular(ADC1); adc_set_right_aligned(ADC1); adc_set_regular_sequence(ADC1, ADC_NUM_CHANNELS, channels); adc_calibrate(ADC1); // configure DMA for ADC //nvic_enable_irq(NVIC_DMA1_STREAM5_IRQ); dma_channel_reset(DMA1, DMA_CHANNEL1); dma_set_priority(DMA1, DMA_CHANNEL1, DMA_CCR_PL_LOW); dma_set_memory_size(DMA1, DMA_CHANNEL1, DMA_CCR_MSIZE_16BIT); dma_set_peripheral_size(DMA1, DMA_CHANNEL1, DMA_CCR_PSIZE_16BIT); dma_enable_memory_increment_mode(DMA1, DMA_CHANNEL1); dma_enable_circular_mode(DMA1, DMA_CHANNEL1); dma_set_read_from_peripheral(DMA1, DMA_CHANNEL1); dma_set_peripheral_address(DMA1, DMA_CHANNEL1, (uint32_t) &ADC1_DR); /* The array adc_values[] is filled with the waveform data to be output */ dma_set_memory_address(DMA1, DMA_CHANNEL1, (uint32_t) adc_values); dma_set_number_of_data(DMA1, DMA_CHANNEL1, ADC_NUM_CHANNELS); //dma_enable_transfer_complete_interrupt(DMA1, DMA_CHANNEL1); dma_enable_channel(DMA1, DMA_CHANNEL1); adc_enable_dma(ADC1); adc_power_on(ADC1); } void measurement_start(void) { // start the ADC conversion sequency. The result will be transferred to RAM // by the DMA. adc_start_conversion_regular(ADC1); } void measurement_wait_for_completion(void) { // wait for DMA transfer to complete while(!dma_get_interrupt_flag(DMA1, DMA_CHANNEL1, DMA_TCIF)); dma_clear_interrupt_flags(DMA1, DMA_CHANNEL1, DMA_TCIF); } void measurement_finalize(struct MeasurementResult *result) { result->u_bat = convert_voltage_divider(adc_values[ANALOG_INPUT_U_BAT], FXP_FROM_INT(220), FXP_FROM_INT(22), calibration_factors[ANALOG_INPUT_U_BAT]); result->u_solar = convert_voltage_divider(adc_values[ANALOG_INPUT_U_SOLAR], FXP_FROM_INT(330), FXP_FROM_INT(22), calibration_factors[ANALOG_INPUT_U_SOLAR]); result->u_sw = convert_voltage_divider(adc_values[ANALOG_INPUT_U_SW], FXP_FROM_INT(1000), FXP_FROM_INT(47), calibration_factors[ANALOG_INPUT_U_SW]); result->i_solar = convert_ina139(adc_values[ANALOG_INPUT_I_SOLAR], fxp_div(FXP_FROM_INT(2), FXP_FROM_INT(1000)), FXP_FROM_INT(56), calibration_factors[ANALOG_INPUT_I_SOLAR]); result->i_load = convert_ina139(adc_values[ANALOG_INPUT_I_LOAD], fxp_div(FXP_FROM_INT(5), FXP_FROM_INT(1000)), FXP_FROM_INT(56), calibration_factors[ANALOG_INPUT_I_LOAD]); result->temperature = calc_temperature(adc_values[5]); /* calculate exponentially averaged values */ result->avg_u_bat = fxp_add( fxp_mult(avg_alpha_u_bat, result->u_bat), fxp_mult(avg_alpha_u_bat_inv, result->avg_u_bat)); result->avg_u_solar = fxp_add( fxp_mult(avg_alpha_u_solar, result->u_solar), fxp_mult(avg_alpha_u_solar_inv, result->avg_u_solar)); result->avg_u_sw = fxp_add( fxp_mult(avg_alpha_u_sw, result->u_sw), fxp_mult(avg_alpha_u_sw_inv, result->avg_u_sw)); result->avg_i_solar = fxp_add( fxp_mult(avg_alpha_i_solar, result->i_solar), fxp_mult(avg_alpha_i_solar_inv, result->avg_i_solar)); result->avg_i_load = fxp_add( fxp_mult(avg_alpha_i_load, result->i_load), fxp_mult(avg_alpha_i_load_inv, result->avg_i_load)); result->avg_temperature = fxp_add( fxp_mult(avg_alpha_temp, result->temperature), fxp_mult(avg_alpha_temp_inv, result->avg_temperature)); }