checkpoint: working sensor acquisition and axis validation

2026-08-17 09:38:18 -04:00
commit f1ac20fb4f
16 changed files with 721 additions and 0 deletions
@@ -0,0 +1,152 @@
+#include <inttypes.h>
+#include <stdio.h>
+
+#include "adxl345.h"
+#include "driver/gpio.h"
+#include "driver/i2c_master.h"
+#include "esp_err.h"
+#include "esp_log.h"
+#include "esp_timer.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "l3g4200d.h"
+
+// Seeed Studio XIAO ESP32-C3: D4/SDA = GPIO6, D5/SCL = GPIO7.
+#define TRIKKE_I2C_PORT       I2C_NUM_0
+#define TRIKKE_I2C_SDA_GPIO   GPIO_NUM_6
+#define TRIKKE_I2C_SCL_GPIO   GPIO_NUM_7
+#define TRIKKE_I2C_FREQ_HZ    400000
+#define TRIKKE_SAMPLE_RATE_HZ 100
+#define TRIKKE_SAMPLE_TICKS   pdMS_TO_TICKS(1000 / TRIKKE_SAMPLE_RATE_HZ)
+
+static const char *TAG = "trikke";
+
+typedef struct {
+    int32_t x;
+    int32_t y;
+    int32_t z;
+} trikke_axes_sample_t;
+
+static trikke_axes_sample_t map_accel_to_enclosure(const adxl345_sample_t *native)
+{
+    // Enclosure frame: +X right, +Y toward the top, +Z toward the cover.
+    // Mounted ADXL345: native +Y right, native +X down, native +Z toward cover.
+    return (trikke_axes_sample_t) {
+        .x = native->y,
+        .y = -(int32_t)native->x,
+        .z = native->z,
+    };
+}
+
+static trikke_axes_sample_t map_gyro_to_enclosure(const l3g4200d_sample_t *native)
+{
+    // The mounted L3G4200D axes already match the enclosure frame.
+    return (trikke_axes_sample_t) {
+        .x = native->x,
+        .y = native->y,
+        .z = native->z,
+    };
+}
+
+static esp_err_t init_i2c(i2c_master_bus_handle_t *bus)
+{
+    const i2c_master_bus_config_t config = {
+        .i2c_port = TRIKKE_I2C_PORT,
+        .sda_io_num = TRIKKE_I2C_SDA_GPIO,
+        .scl_io_num = TRIKKE_I2C_SCL_GPIO,
+        .clk_source = I2C_CLK_SRC_DEFAULT,
+        .glitch_ignore_cnt = 7,
+        .flags.enable_internal_pullup = true,
+    };
+
+    return i2c_new_master_bus(&config, bus);
+}
+
+void app_main(void)
+{
+    // Emit each CSV record immediately while testing over USB.
+    setvbuf(stdout, NULL, _IOLBF, 0);
+
+    ESP_LOGI(TAG, "Trikke motion telemetry prototype v0");
+    ESP_LOGI(TAG, "I2C: SDA=GPIO%d, SCL=GPIO%d, clock=%d Hz",
+             TRIKKE_I2C_SDA_GPIO, TRIKKE_I2C_SCL_GPIO, TRIKKE_I2C_FREQ_HZ);
+
+    i2c_master_bus_handle_t bus = NULL;
+    esp_err_t err = init_i2c(&bus);
+    if (err != ESP_OK) {
+        ESP_LOGE(TAG, "I2C initialization failed: %s", esp_err_to_name(err));
+        return;
+    }
+
+    adxl345_t accelerometer = {0};
+    err = adxl345_init(&accelerometer, bus, TRIKKE_I2C_FREQ_HZ);
+    if (err != ESP_OK) {
+        ESP_LOGE(TAG,
+                 "ADXL345 not found at 0x53 or 0x1D (expected DEVID 0xE5): %s",
+                 esp_err_to_name(err));
+        return;
+    }
+    ESP_LOGI(TAG, "ADXL345 detected at 0x%02X; 100 Hz, +/-8 g, full resolution",
+             adxl345_address(&accelerometer));
+
+    l3g4200d_t gyroscope = {0};
+    err = l3g4200d_init(&gyroscope, bus, TRIKKE_I2C_FREQ_HZ);
+    if (err != ESP_OK) {
+        ESP_LOGE(TAG,
+                 "L3G4200D not found at 0x69 or 0x68 (expected WHO_AM_I 0xD3): %s",
+                 esp_err_to_name(err));
+        return;
+    }
+    ESP_LOGI(TAG, "L3G4200D detected at 0x%02X; 100 Hz, 25 Hz BW, +/-500 dps",
+             l3g4200d_address(&gyroscope));
+
+    // Discard the gyroscope's visible startup transient before beginning the stream.
+    vTaskDelay(pdMS_TO_TICKS(500));
+
+    printf("# format=trikke_axis_validation_v1\n");
+    printf("# accel_scale_g_per_lsb=0.0039,gyro_scale_dps_per_lsb=0.0175\n");
+    printf("# enclosure_axes=+x:right,+y:top,+z:toward_cover\n");
+    printf("# mapping=accel(x,y,z)=(native_y,-native_x,native_z);"
+           "gyro(x,y,z)=(native_x,native_y,native_z)\n");
+    printf("sequence,timestamp_us,accel_x_raw,accel_y_raw,accel_z_raw,"
+           "gyro_x_raw,gyro_y_raw,gyro_z_raw,"
+           "accel_native_x_raw,accel_native_y_raw,accel_native_z_raw,"
+           "gyro_native_x_raw,gyro_native_y_raw,gyro_native_z_raw\n");
+
+    uint32_t sequence = 0;
+    uint32_t read_error_count = 0;
+    TickType_t last_wake = xTaskGetTickCount();
+
+    while (true) {
+        adxl345_sample_t accel = {0};
+        l3g4200d_sample_t gyro = {0};
+        const int64_t timestamp_us = esp_timer_get_time();
+
+        const esp_err_t accel_err = adxl345_read_raw(&accelerometer, &accel);
+        const esp_err_t gyro_err = l3g4200d_read_raw(&gyroscope, &gyro);
+
+        if (accel_err == ESP_OK && gyro_err == ESP_OK) {
+            const trikke_axes_sample_t enclosure_accel = map_accel_to_enclosure(&accel);
+            const trikke_axes_sample_t enclosure_gyro = map_gyro_to_enclosure(&gyro);
+
+            printf("%" PRIu32 ",%" PRId64 ",%" PRId32 ",%" PRId32 ",%" PRId32
+                   ",%" PRId32 ",%" PRId32 ",%" PRId32
+                   ",%" PRId16 ",%" PRId16 ",%" PRId16
+                   ",%" PRId16 ",%" PRId16 ",%" PRId16 "\n",
+                   sequence, timestamp_us,
+                   enclosure_accel.x, enclosure_accel.y, enclosure_accel.z,
+                   enclosure_gyro.x, enclosure_gyro.y, enclosure_gyro.z,
+                   accel.x, accel.y, accel.z,
+                   gyro.x, gyro.y, gyro.z);
+        } else {
+            ++read_error_count;
+            ESP_LOGE(TAG,
+                     "sample %" PRIu32 " read failed (accel=%s, gyro=%s, total_errors=%" PRIu32 ")",
+                     sequence, esp_err_to_name(accel_err), esp_err_to_name(gyro_err),
+                     read_error_count);
+        }
+
+        ++sequence;
+        xTaskDelayUntil(&last_wake, TRIKKE_SAMPLE_TICKS);
+    }
+}