Current sensing

firmware/PowerDistributionUnit_Mk1/core/inc/PDU_Mk1_CurrentSensing.h

@@ -0,0 +1,83 @@
+// PDU_Mk1_CurrentSensing.h
+// ----------------------------------------------------------------------------
+// Stuff for output current sensing on BBPDU. 
+
+#pragma once
+
+// INCLUDES -------------------------------------------------------------------
+
+#include "stm32xx_hal.h"
+
+// BBPDU peripherals
+#include "PDU_Mk1.h"
+#include "PDU_Mk1_Pins.h"
+
+// drivers
+#include "ADS131M08-Q1.h"
+#include "ACS3704x-010B3.h"
+
+// DEFINES --------------------------------------------------------------------
+
+#define CURRENT_SENSING_OFFSET_CALC_NUMSAMPLES 20			// number of samples used for calculating no-current offset
+#define CURRENT_SENSING_OFFSET_CALC_SAMPLE_DELAY_MS 100		// [ms] delay between samples for calculating no-current offset
+
+// VARIABLE DECLARATIONS ------------------------------------------------------
+
+extern SPI_HandleTypeDef hspi2;
+extern SemaphoreHandle_t spi2_mutex;
+extern StaticSemaphore_t spi2_mutex_buffer;
+extern SemaphoreHandle_t spi2_done_sem;
+
+extern SPI_HandleTypeDef hspi3;
+extern SemaphoreHandle_t spi3_mutex;
+extern StaticSemaphore_t spi3_mutex_buffer;
+extern SemaphoreHandle_t spi3_done_sem;
+
+extern float currents[PDU_MK1_NUM_CHANNELS];
+extern float current_adc_v_offset[PDU_MK1_NUM_CHANNELS];
+
+// FUNCTIONS ------------------------------------------------------------------
+
+/**
+	* @brief Initializes current sensing functions (ADCs, initial calibration-TODO). 
+	* Must be called while all outputs are disabled. 
+	* @param None
+	* @retval bool: true if successful, false otherwise
+	*/
+bool PDU_Mk1_CurrentSensing_Init();
+
+/**
+	* @brief Initializes ADC_SNS1 for current sensing use. 
+	* @param None
+	* @retval ADS131M08Q1 Status (ADS131M08Q1_🙂 if successful)
+	*/
+ADS131M08Q1_Status_t PDU_Mk1_Init_ADC_SNS0();
+
+/**
+	* @brief Initializes ADC_SNS1 for current sensing use. 
+	* @param None
+	* @retval ADS131M08Q1 Status (ADS131M08Q1_🙂 if successful)
+	*/
+ADS131M08Q1_Status_t PDU_Mk1_Init_ADC_SNS1();
+
+/**
+	* @brief Reads current sensing ADCs under zero-current conditions to get offset. 
+	* Must only be run while all high-side switches are off.
+	* @param None
+	* @retval bool: true if successful, false otherwise
+	*/
+bool PDU_Mk1_CurrentSensing_CollectOffsets();
+
+/**
+	* @brief Reads sample from current sensing ADCs and calculates current conversion.
+	* @param None
+	* @retval bool: true if successful, false otherwise
+	*/
+bool PDU_Mk1_CurrentSensing_ReadCurrents();
+
+/**
+	* @brief Returns pointer to array where last currents sample is stored. 
+	* @param None
+	* @retval float pointer to currents array
+	*/
+float* PDU_Mk1_CurrentSensing_GetCurrentsPtr();

firmware/PowerDistributionUnit_Mk1/core/src/PDU_Mk1_Current_Sensing.c → firmware/PowerDistributionUnit_Mk1/core/src/PDU_Mk1_CurrentSensing.c

@@ -1,14 +1,14 @@
-// PDU_Mk1_Current_Sensing.c
+// PDU_Mk1_CurrentSensing.c
 
-#include "PDU_Mk1_Current_Sensing.h"
+#include "PDU_Mk1_CurrentSensing.h"
 
 ADS131M08Q1_HandleTypeDef adc_sns1;
 ADS131M08Q1_HandleTypeDef adc_sns0;
 
 float currents[PDU_MK1_NUM_CHANNELS] = {0};
-float current_offset[PDU_MK1_NUM_CHANNELS] = {0};
+float current_adc_v_offset[PDU_MK1_NUM_CHANNELS] = {0};
 
-bool PDU_Mk1_Current_Sensing_Init()
+bool PDU_Mk1_CurrentSensing_Init()
 {
     if(PDU_Mk1_Init_ADC_SNS0() != ADS131M08Q1_🙂)
     {
@@ -20,6 +20,11 @@ bool PDU_Mk1_Current_Sensing_Init()
         return false;
     }
 
+    if(PDU_Mk1_CurrentSensing_CollectOffsets() != true)
+    {
+        return false;
+    }
+
     return true;
 }
 
@@ -74,8 +79,72 @@ ADS131M08Q1_Status_t PDU_Mk1_Init_ADC_SNS1()
     adc_sns1.config.fsr = ADS131M08Q1_INTERNAL_REFERENCE_V;
     adc_sns1.config.powermode = ADS131M08Q1_CONFIG_POWERMODE_DEFAULT;
 
-    // channel 0 reads about 0.24 V high for some reason (rev A only)
-    // adc_sns1.config.ch_configs[0].offset_cal = ADS131M08Q1_CalcOffsetCalRegValue(&adc_sns1, -0.24);
-
     return ADS131M08Q1_Init(&adc_sns1);
 }
+
+bool PDU_Mk1_CurrentSensing_CollectOffsets()
+{
+    float adc_results_sns0[CURRENT_SENSING_OFFSET_CALC_NUMSAMPLES][ADS131M08Q1_NUM_CHANNELS] = {0};
+    float adc_results_sns1[CURRENT_SENSING_OFFSET_CALC_NUMSAMPLES][ADS131M08Q1_NUM_CHANNELS] = {0};
+
+    for(uint8_t sample = 0; sample < CURRENT_SENSING_OFFSET_CALC_NUMSAMPLES; sample++)
+    {
+        if(ADS131M08Q1_ReadConversionResults(&adc_sns0, adc_results_sns0[sample]) != ADS131M08Q1_🙂)
+        {
+            return false;
+        }
+
+        if(ADS131M08Q1_ReadConversionResults(&adc_sns1, adc_results_sns1[sample]) != ADS131M08Q1_🙂)
+        {
+            return false;
+        }
+
+        if(sample != CURRENT_SENSING_OFFSET_CALC_NUMSAMPLES-1)
+        {
+            vTaskDelay(pdMS_TO_TICKS(CURRENT_SENSING_OFFSET_CALC_SAMPLE_DELAY_MS));
+        }
+    }
+
+    for(uint8_t ch = 0; ch < ADS131M08Q1_NUM_CHANNELS; ch++)
+    {
+        for(uint8_t sample = 0; sample < CURRENT_SENSING_OFFSET_CALC_NUMSAMPLES; sample++)
+        {
+            current_adc_v_offset[ch] += -1.0*adc_results_sns1[sample][(ADS131M08Q1_NUM_CHANNELS-1)-ch];
+            current_adc_v_offset[ADS131M08Q1_NUM_CHANNELS+ch] += -1.0*adc_results_sns0[sample][(ADS131M08Q1_NUM_CHANNELS-1)-ch];
+        }
+
+        current_adc_v_offset[ch] /= (float) CURRENT_SENSING_OFFSET_CALC_NUMSAMPLES;
+        current_adc_v_offset[ADS131M08Q1_NUM_CHANNELS+ch] /= (float) CURRENT_SENSING_OFFSET_CALC_NUMSAMPLES;
+    }
+
+    return true;
+}
+
+bool PDU_Mk1_CurrentSensing_ReadCurrents()
+{
+    float adc_results_sns0[ADS131M08Q1_NUM_CHANNELS] = {0};
+    float adc_results_sns1[ADS131M08Q1_NUM_CHANNELS] = {0};
+
+    if(ADS131M08Q1_ReadConversionResults(&adc_sns0, adc_results_sns0) != ADS131M08Q1_🙂)
+    {
+        return false;
+    }
+
+    if(ADS131M08Q1_ReadConversionResults(&adc_sns1, adc_results_sns1) != ADS131M08Q1_🙂)
+    {
+        return false;
+    }
+
+    for(uint8_t i = 0; i < ADS131M08Q1_NUM_CHANNELS; i++)
+    {
+        currents[i] = ACS3704x_010B3_Current_Conversion_QVOCentered(adc_results_sns1[(ADS131M08Q1_NUM_CHANNELS-1)-i]+current_adc_v_offset[i]);
+        currents[ADS131M08Q1_NUM_CHANNELS+i] = ACS3704x_010B3_Current_Conversion_QVOCentered(adc_results_sns0[(ADS131M08Q1_NUM_CHANNELS-1)-i]+current_adc_v_offset[ADS131M08Q1_NUM_CHANNELS+i]);
+    }
+
+    return true;
+}
+
+float* PDU_Mk1_CurrentSensing_GetCurrentsPtr()
+{
+    return currents;
+}