ltc1865 driver

docs/.pages

@@ -3,3 +3,4 @@ nav:
     - micro-libs.md
     - blinky
     - bms-monitor
+    - ltc1865

docs/ltc1865/.pages

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+title: Ltc1865
+nav:
+    - ltc1865.md

docs/ltc1865/ltc1865.md

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+# Ltc1865
+
+This is a typical voltage reading function for the ltc1865 chip.
+
+```c
+float acquisinator_read_voltage() {
+  HAL_StatusTypeDef spi_status = HAL_ERROR;
+  HAL_GPIO_WritePin(SPI_CS_GPIO_Port, SPI_CS_Pin, GPIO_PIN_RESET);
+  uint8_t out[2] = {0};
+  size_t byte_count = ltc1865_select_channel_encode(LTC1865L_SE_CH1, out);
+  spi_status = HAL_SPI_Transmit(&hspi1, out, byte_count, SPI_DEFAULT_TIMEOUT);
+  acquisinator_spi_error_handler(spi_status);
+  HAL_GPIO_WritePin(SPI_CS_GPIO_Port, SPI_CS_Pin, GPIO_PIN_SET);
+  uint16_t cell_value = 0;
+  HAL_GPIO_WritePin(SPI_CS_GPIO_Port, SPI_CS_Pin, GPIO_PIN_RESET);
+  spi_status =
+      HAL_SPI_Receive(&hspi1, (uint8_t *)&cell_value, 2, SPI_DEFAULT_TIMEOUT);
+  acquisinator_spi_error_handler(spi_status);
+  HAL_GPIO_WritePin(SPI_CS_GPIO_Port, SPI_CS_Pin, GPIO_PIN_SET);
+  return ltc1865_voltage_decode(LTC1865L_SE_CH1, cell_value);
+}
+```
+

ltc1865/README.md

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+# LTC1865
+
+This is a typical voltage reading function for the ltc1865 chip.
+
+```c
+float acquisinator_read_voltage() {
+  HAL_StatusTypeDef spi_status = HAL_ERROR;
+  HAL_GPIO_WritePin(SPI_CS_GPIO_Port, SPI_CS_Pin, GPIO_PIN_RESET);
+  uint8_t out[2] = {0};
+  size_t byte_count = ltc1865_select_channel_encode(LTC1865L_SE_CH1, out);
+  spi_status = HAL_SPI_Transmit(&hspi1, out, byte_count, SPI_DEFAULT_TIMEOUT);
+  acquisinator_spi_error_handler(spi_status);
+  HAL_GPIO_WritePin(SPI_CS_GPIO_Port, SPI_CS_Pin, GPIO_PIN_SET);
+  uint16_t cell_value = 0;
+  HAL_GPIO_WritePin(SPI_CS_GPIO_Port, SPI_CS_Pin, GPIO_PIN_RESET);
+  spi_status =
+      HAL_SPI_Receive(&hspi1, (uint8_t *)&cell_value, 2, SPI_DEFAULT_TIMEOUT);
+  acquisinator_spi_error_handler(spi_status);
+  HAL_GPIO_WritePin(SPI_CS_GPIO_Port, SPI_CS_Pin, GPIO_PIN_SET);
+  return ltc1865_voltage_decode(LTC1865L_SE_CH1, cell_value);
+}
+```

ltc1865/inc/ltc1865.h

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+/**
+ * @file ltc1865.h
+ * @brief
+ *
+ * @date 10 Feb 2024
+ * @author Giacomo Mazzucchi [[email protected]]
+ */
+
+#ifndef LTC1865_H
+#define LTC1865_H
+
+#include <stddef.h>
+#include <stdint.h>
+
+/**
+ * For a typical application you want to use LTC1865L_SE_CH1 and LTC1865L_SE_CH2
+ */
+typedef enum {
+  LTC1865L_DIFF,
+  LTC1865L_DIFF_INVERTED,
+  LTC1865L_SE_CH1,
+  LTC1865L_SE_CH2,
+  LTC1865_N_CHANNELS
+} ltc1865_channel_t;
+
+/**
+ * Please note that `uint8_t *out` must be 2 byte long.
+ */
+size_t ltc1865_select_channel_encode(ltc1865_channel_t channel, uint8_t *out);
+
+float ltc1865_voltage_decode(ltc1865_channel_t channel, uint16_t raw_data);
+
+#endif // LTC1865_H

ltc1865/src/ltc1865.c

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+/**
+ * @file ltc1865.c
+ * @brief
+ *
+ * @date 10 Feb 2024
+ * @author Giacomo Mazzucchi [[email protected]]
+ */
+
+#include "ltc1865.h"
+
+#define LTC1865_VREF_INT 3300
+
+/**
+ * Please note that `uint8_t *out` must be 2 byte long.
+ */
+size_t ltc1865_select_channel_encode(ltc1865_channel_t channel, uint8_t *out) {
+  if (out == NULL) {
+    return 0U;
+  }
+  switch (channel) {
+  case LTC1865L_SE_CH1:
+    out[0] = 0xFF;
+    out[1] = 0xFF;
+    break;
+  case LTC1865L_SE_CH2:
+    out[0] = 0xAA;
+    out[1] = 0xAA;
+    break;
+  case LTC1865L_DIFF:
+    out[0] = 0x00;
+    out[1] = 0x00;
+    break;
+  case LTC1865L_DIFF_INVERTED:
+    out[0] = 0x55;
+    out[1] = 0x55;
+    break;
+  default:
+    return 0U;
+  }
+  return 2U;
+}
+
+float ltc1865_voltage_decode(ltc1865_channel_t channel, uint16_t raw_data) {
+  return (LTC1865_VREF_INT -
+          ((((raw_data << 8) | (raw_data >> 8)) * LTC1865_VREF_INT) /
+           (UINT16_MAX)));
+}

ltc1865/test/Makefile

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+.PHONY: all test_all clear
+
+# Build directories
+BUILD_DIR=build
+BUILD_DEPS_DIR=$(BUILD_DIR)/deps
+
+# Source and include directories
+SRC_DIR=../src
+INC_DIR=../inc
+UNITY_DIR=../../Unity/src
+
+# Tools
+CC=$(shell command -v gcc || command -v clang || echo /bin/gcc)
+SZ=$(shell command -v size)
+
+# Sources
+C_SOURCES=$(wildcard *.c)
+DEPS_SOURCES=$(wildcard $(SRC_DIR)/*.c $(UNITY_DIR)/unity.c)
+SOURCES=$(C_SOURCES) $(DEPS_SOURCES)
+
+# Include directories
+C_INCLUDES= \
+$(UNITY_DIR) \
+$(INC_DIR)
+
+# Executables
+TARGETS=$(addprefix $(BUILD_DIR)/, $(basename $(C_SOURCES)))
+
+OPT=-Og
+
+C_DEFINES= \
+UNITY_OUTPUT_COLOR=1
+
+
+CFLAGS=$(addprefix -I,$(C_INCLUDES)) $(OPT) -Wall $(addprefix -D,$(C_DEFINES))
+
+# List of object files
+C_OBJECTS=$(addprefix $(BUILD_DIR)/, $(notdir $(C_SOURCES:.c=.o)))
+DEPS_OBJECTS=$(addprefix $(BUILD_DIR)/, $(notdir $(DEPS_SOURCES:.c=.o) $(UNITY_SOURCES:.c=.o)))
+OBJECTS=$(C_OBJECTS) $(DEPS_OBJECTS)
+vpath %.c $(sort $(dir $(SOURCES)))
+
+# File with the final test results
+TEST_RESULTS=$(BUILD_DIR)/result.txt
+
+all: $(TARGETS)
+
+# Build
+$(TARGETS): $(OBJECTS) Makefile
+	$(CC) $@.o $(DEPS_OBJECTS) -o $@
+
+$(BUILD_DEPS_DIR)/%.o: %.c Makefile | $(BUILD_DIR)
+	$(CC) -c $(CFLAGS) $< -o $@
+
+$(BUILD_DIR)/%.o: %.c Makefile | $(BUILD_DIR)
+	$(CC) -c $(CFLAGS) $< -o $@
+
+$(BUILD_DIR): $(BUILD_DEPS_DIR)
+
+$(BUILD_DEPS_DIR):
+	mkdir -p $@
+
+# Run all tests
+test_all: $(TARGETS)
+	@echo -n "" > $(TEST_RESULTS)
+	@for target in $?; do \
+		./$$target | tee -a $(TEST_RESULTS); \
+	done
+
+# Clean all
+clean:
+	rm -rf $(BUILD_DIR)
+

ltc1865/test/test-ltc1865.c

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+/**
+ * @file test-ltc1865.c
+ * @brief
+ *
+ * @date 10 Feb 2024
+ * @author Giacomo Mazzucchi [[email protected]]
+ */
+
+#include "ltc1865.h"
+#include "unity.h"
+
+void setUp(void) {}
+
+void tearDown(void) {}
+
+void test_unity(void) { TEST_ASSERT(1); }
+
+int main() {
+  UNITY_BEGIN();
+
+  RUN_TEST(test_unity);
+
+  UNITY_END();
+}