diff --git a/Documentation/index.rst b/Documentation/index.rst
index d9a7339a5fcb8f241fad2a66395d91ed318123f9..69e8cb9f07b0814aad4ac326142acff423eda5db 100644
--- a/Documentation/index.rst
+++ b/Documentation/index.rst
@@ -21,6 +21,7 @@ Last but not least, if you want to start hacking the lower-level firmware, the
:caption: Pycardium
pycardium/overview
+ pycardium/bma400
pycardium/color
pycardium/leds
pycardium/vibra
diff --git a/Documentation/pycardium/bma400.rst b/Documentation/pycardium/bma400.rst
new file mode 100644
index 0000000000000000000000000000000000000000..77e5390a57c88edc97b0376e92444cf0d47a8ba1
--- /dev/null
+++ b/Documentation/pycardium/bma400.rst
@@ -0,0 +1,8 @@
+``bma400`` - Accelerometer
+==========================
+
+.. py:function:: bma400.get_accel()
+
+ Get acceleration vector.
+
+ :return: Tuple containing ``x``, ``y``, and ``z`` acceleration.
diff --git a/epicardium/epicardium.h b/epicardium/epicardium.h
index 4e52d85c51c38d897f38dbee03ed96cbbb7b0de1..7c0ce6d33038bf51cbad4abfb564610d4e1aa5da 100644
--- a/epicardium/epicardium.h
+++ b/epicardium/epicardium.h
@@ -15,6 +15,7 @@
#define API_VIBRA_SET 0x4
#define API_VIBRA_VIBRATE 0x5
#define API_STREAM_READ 0x6
+#define API_BMA400_GET_ACCEL 0x99
/* clang-format on */
/**
@@ -120,6 +121,37 @@ API(API_LEDS_SET, void epic_leds_set(int led, uint8_t r, uint8_t g, uint8_t b));
*/
API(API_STREAM_READ, int epic_stream_read(int sd, void *buf, size_t count));
+/**
+ * BMA400
+ * ======
+ */
+
+/**
+ * An acceleration vector.
+ */
+struct acceleration {
+ /** Acceleration component along x axis. */
+ float x;
+ /** Acceleration component along y axis. */
+ float y;
+ /** Acceleration component along z axis. */
+ float z;
+};
+
+/**
+ * Get the current acceleration vector.
+ *
+ * :param data: Where to store the acceleration vector.
+ * :return: 0 on success or ``-Exxx`` on error. The following
+ * errors might occur:
+ *
+ * - ``-EFAULT``: On NULL-pointer.
+ * - ``-EINVAL``: Invalid configuration.
+ * - ``-EIO``: Communication with the device failed.
+ * - ``-ENODEV``: Device was not found.
+ */
+API(API_BMA400_GET_ACCEL, int epic_bma400_get_accel(struct acceleration *data));
+
/**
* Misc
* ====
diff --git a/epicardium/modules/bma400.c b/epicardium/modules/bma400.c
new file mode 100644
index 0000000000000000000000000000000000000000..8520aa68e41fa7cf8f759268db6434bb116f72c0
--- /dev/null
+++ b/epicardium/modules/bma400.c
@@ -0,0 +1,104 @@
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdio.h>
+
+#include "bma400.h"
+#include "bosch.h"
+#include "card10.h"
+
+#include "epicardium.h"
+#include "modules/log.h"
+
+static bool initialized;
+static struct bma400_dev bma400;
+
+#define GRAVITY_EARTH (9.80665f) /* Earth's gravity in m/s^2 */
+static float lsb_to_ms2(int16_t val, float g_range, uint8_t bit_width)
+{
+ float half_scale = (float)(1 << bit_width) / 2.0f;
+ return GRAVITY_EARTH * val * g_range / half_scale;
+}
+
+static int convert_error(int8_t error)
+{
+ switch (error) {
+ case BMA400_E_NULL_PTR:
+ return EFAULT;
+ case BMA400_E_COM_FAIL:
+ return EIO;
+ case BMA400_E_DEV_NOT_FOUND:
+ return ENODEV;
+ case BMA400_E_INVALID_CONFIG:
+ return EINVAL;
+ default:
+ return 1;
+ }
+}
+
+int epic_bma400_get_accel(struct acceleration *data)
+{
+ uint8_t result;
+
+ if (__builtin_expect(!initialized, 0)) {
+ bma400.intf_ptr = NULL;
+ bma400.delay_ms = card10_bosch_delay;
+ bma400.dev_id = BMA400_I2C_ADDRESS_SDO_LOW;
+ bma400.read = card10_bosch_i2c_read_ex;
+ bma400.write = card10_bosch_i2c_write_ex;
+ bma400.intf = BMA400_I2C_INTF;
+
+ result = bma400_init(&bma400);
+ if (result != BMA400_OK) {
+ LOG_ERR("bma400", "init error: %d", result);
+ return -convert_error(result);
+ }
+
+ result = bma400_soft_reset(&bma400);
+ if (result != BMA400_OK) {
+ LOG_ERR("bma400", "soft_reset error: %d", result);
+ return -convert_error(result);
+ }
+
+ struct bma400_sensor_conf conf;
+ conf.type = BMA400_ACCEL;
+
+ result = bma400_get_sensor_conf(&conf, 1, &bma400);
+ if (result != BMA400_OK) {
+ LOG_ERR("bma400", "get_sensor_conf error: %d", result);
+ return -convert_error(result);
+ }
+
+ conf.param.accel.odr = BMA400_ODR_100HZ;
+ conf.param.accel.range = BMA400_2G_RANGE;
+ conf.param.accel.data_src = BMA400_DATA_SRC_ACCEL_FILT_1;
+
+ result = bma400_set_sensor_conf(&conf, 1, &bma400);
+ if (result != BMA400_OK) {
+ LOG_ERR("bma400", "set_sensor_conf error: %d", result);
+ return -convert_error(result);
+ }
+
+ result = bma400_set_power_mode(BMA400_LOW_POWER_MODE, &bma400);
+ if (result != BMA400_OK) {
+ LOG_ERR("bma400", "set_power_mode error: %d", result);
+ return -convert_error(result);
+ }
+
+ initialized = true;
+ }
+
+ struct bma400_sensor_data data_in;
+ result = bma400_get_accel_data(
+ BMA400_DATA_SENSOR_TIME, &data_in, &bma400
+ );
+ if (result != BMA400_OK) {
+ LOG_ERR("bma400", "get_accel_data error: %d\n", result);
+ return -convert_error(result);
+ }
+
+ data->x = lsb_to_ms2(data_in.x, 2, 12);
+ data->y = lsb_to_ms2(data_in.y, 2, 12);
+ data->z = lsb_to_ms2(data_in.z, 2, 12);
+
+ return 0;
+}
diff --git a/epicardium/modules/meson.build b/epicardium/modules/meson.build
index a038fb21d7f5ef7c650a10851503150a27c0b1eb..42e1c7aed16da454684ef54cd263b0c5f201975f 100644
--- a/epicardium/modules/meson.build
+++ b/epicardium/modules/meson.build
@@ -1,5 +1,6 @@
module_sources = files(
'fatfs.c',
+ 'bma400.c',
'leds.c',
'log.c',
'pmic.c',
diff --git a/pycardium/meson.build b/pycardium/meson.build
index 67698112ed8be52f569fec2d4d087371bbe5cb91..371a0017ccd525990e0495fbf78acb3d49bccc13 100644
--- a/pycardium/meson.build
+++ b/pycardium/meson.build
@@ -2,6 +2,7 @@ name = 'pycardium'
modsrc = files(
'modules/utime.c',
+ 'modules/bma400.c',
'modules/leds.c',
'modules/vibra.c',
)
diff --git a/pycardium/modules/bma400.c b/pycardium/modules/bma400.c
new file mode 100644
index 0000000000000000000000000000000000000000..e09e169534d4e4403df8a7cf1cd73c101f46c1e6
--- /dev/null
+++ b/pycardium/modules/bma400.c
@@ -0,0 +1,37 @@
+#include "py/obj.h"
+#include "py/objlist.h"
+#include "py/runtime.h"
+
+#include "epicardium.h"
+
+static mp_obj_t mp_bma400_get_accel()
+{
+ struct acceleration values;
+ int ret = epic_bma400_get_accel(&values);
+
+ if (ret < 0) {
+ mp_raise_OSError(-ret);
+ }
+
+ mp_obj_t values_list[] = {
+ mp_obj_new_float(values.x),
+ mp_obj_new_float(values.y),
+ mp_obj_new_float(values.z),
+ };
+ return mp_obj_new_tuple(3, values_list);
+}
+static MP_DEFINE_CONST_FUN_OBJ_0(bma400_get_accel_obj, mp_bma400_get_accel);
+
+static const mp_rom_map_elem_t bma400_module_globals_table[] = {
+ { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_bma400) },
+ { MP_ROM_QSTR(MP_QSTR_get_accel), MP_ROM_PTR(&bma400_get_accel_obj) },
+};
+static MP_DEFINE_CONST_DICT(bma400_module_globals, bma400_module_globals_table);
+
+const mp_obj_module_t bma400_module = {
+ .base = { &mp_type_module },
+ .globals = (mp_obj_dict_t *)&bma400_module_globals,
+};
+
+/* Register the module to make it available in Python */
+MP_REGISTER_MODULE(MP_QSTR_bma400, bma400_module, MODULE_BMA400_ENABLED);
diff --git a/pycardium/modules/qstrdefs.h b/pycardium/modules/qstrdefs.h
index 2a6dcbe6beb7ebe5a4a5a29226b7eca0a6b9c901..faff67e9000d254902b5fc2ce521275789937b85 100644
--- a/pycardium/modules/qstrdefs.h
+++ b/pycardium/modules/qstrdefs.h
@@ -4,6 +4,10 @@
#define Q(x)
#endif
+/* bma400 */
+Q(bma400)
+Q(get_accel)
+
/* leds */
Q(leds)
Q(BOTTOM_LEFT)
diff --git a/pycardium/mpconfigport.h b/pycardium/mpconfigport.h
index a99c63acfe3d50a083b6a428e1b511d41edf13e5..3851faf5028df767dc12472f03acb9fd71010d86 100644
--- a/pycardium/mpconfigport.h
+++ b/pycardium/mpconfigport.h
@@ -37,6 +37,7 @@
/* Modules */
#define MODULE_UTIME_ENABLED (1)
#define MODULE_LEDS_ENABLED (1)
+#define MODULE_BMA400_ENABLED (1)
#define MODULE_VIBRA_ENABLED (1)
/*