Implement SoC estimation (UNTESTED!)

Core/Inc/SPI_Communication.h

@@ -25,7 +25,8 @@
 #define TOGGLE_STATUS_LED 0x06
 
 #define NUMBEROFSLAVES 6
-#define NUMBEROFCELLS 10
+#define N_CELLS_SERIES 10
+#define N_CELLS_PARALLEL 9
 #define NUMBEROFTEMPS 32
 
 #define SLAVE_TIMEOUT 200
@@ -33,7 +34,7 @@
 typedef struct {
 
   uint16_t slaveID;
-  uint16_t cellVoltages[NUMBEROFCELLS];
+  uint16_t cellVoltages[N_CELLS_SERIES];
   uint16_t cellTemps[NUMBEROFTEMPS];
   uint32_t timestamp;
   uint8_t error;

Core/Inc/SoC_Estimation.h

@@ -0,0 +1,15 @@
+#ifndef INC_SOC_ESTIMATION_H
+#define INC_SOC_ESTIMATION_H
+
+#include "SPI_Communication.h"
+
+#define SOCE_SHUNT_CURRENT_OFF_THRESH 20                  /* mA */
+#define CELL_VOLTAGE_CONVERSION_FACTOR 5.0f / 65535       /* V/quantum */
+#define BATTERY_CAPACITY (N_CELLS_PARALLEL * 2.5f * 3600) /* As */
+
+extern uint8_t current_soc;
+
+void estimate_soc();
+float calculate_soc_for_ocv(float ocv);
+
+#endif // INC_SOC_ESTIMATION_H

Core/Inc/util.h

@@ -0,0 +1,17 @@
+#ifndef INC_UTIL_H
+#define INC_UTIL_H
+
+#include <stdint.h>
+
+/**
+ * @brief Perform linear interpolation.
+ *
+ * @param n_points Size of source_x and source_y
+ * @param source_x x values for the interpolation source (sorted ascending)
+ * @param source_y y values corresponding to source_x
+ * @param target_x x value that a y value should be interpolated for
+ */
+float interp(uint32_t n_points, const float* source_x, const float* source_y,
+             float target_x);
+
+#endif // INC_UTIL_H