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#include <stdio.h>
#include <string.h>
#include <stm32f4xx_hal.h>
#include "nlr.h"
#include "misc.h"
#include "mpconfig.h"
#include "qstr.h"
#include "obj.h"
#include "runtime.h"
#include "i2c.h"
#include "accel.h"
#define MMA_ADDR (0x98)
#define MMA_REG_X (0)
#define MMA_REG_Y (1)
#define MMA_REG_Z (2)
#define MMA_REG_TILT (3)
#define MMA_REG_MODE (7)
#define MMA_AXIS_SIGNED_VALUE(i) (((i) & 0x3f) | ((i) & 0x20 ? (~0x1f) : 0))
void accel_init(void) {
GPIO_InitTypeDef GPIO_InitStructure;
// PB5 is connected to AVDD; pull high to enable MMA accel device
GPIOB->BSRRH = GPIO_PIN_5; // turn off AVDD
GPIO_InitStructure.Pin = GPIO_PIN_5;
GPIO_InitStructure.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStructure.Speed = GPIO_SPEED_LOW;
GPIO_InitStructure.Pull = GPIO_NOPULL;
HAL_GPIO_Init(GPIOB, &GPIO_InitStructure);
}
STATIC void accel_start(void) {
// start the I2C bus
i2c_start(&I2cHandle_X);
// turn off AVDD, wait 20ms, turn on AVDD, wait 20ms again
GPIOB->BSRRH = GPIO_PIN_5; // turn off
HAL_Delay(20);
GPIOB->BSRRL = GPIO_PIN_5; // turn on
HAL_Delay(20);
HAL_StatusTypeDef status;
//printf("IsDeviceReady\n");
for (int i = 0; i < 10; i++) {
status = HAL_I2C_IsDeviceReady(&I2cHandle_X, MMA_ADDR, 10, 200);
//printf(" got %d\n", status);
if (status == HAL_OK) {
break;
}
}
//printf("MemWrite\n");
uint8_t data[1];
data[0] = 1; // active mode
status = HAL_I2C_Mem_Write(&I2cHandle_X, MMA_ADDR, MMA_REG_MODE, I2C_MEMADD_SIZE_8BIT, data, 1, 200);
//printf(" got %d\n", status);
}
/******************************************************************************/
/* Micro Python bindings */
#define NUM_AXIS (3)
#define FILT_DEPTH (4)
typedef struct _pyb_accel_obj_t {
mp_obj_base_t base;
int16_t buf[NUM_AXIS * FILT_DEPTH];
} pyb_accel_obj_t;
STATIC pyb_accel_obj_t pyb_accel_obj;
STATIC mp_obj_t pyb_accel_make_new(mp_obj_t type_in, uint n_args, uint n_kw, const mp_obj_t *args) {
// check arguments
mp_check_nargs(n_args, 0, 0, n_kw, false);
// init accel object
pyb_accel_obj.base.type = &pyb_accel_type;
accel_start();
return &pyb_accel_obj;
}
STATIC mp_obj_t read_axis(int axis) {
uint8_t data[1];
HAL_I2C_Mem_Read(&I2cHandle_X, MMA_ADDR, axis, I2C_MEMADD_SIZE_8BIT, data, 1, 200);
return mp_obj_new_int(MMA_AXIS_SIGNED_VALUE(data[0]));
}
STATIC mp_obj_t pyb_accel_x(mp_obj_t self_in) {
return read_axis(MMA_REG_X);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_accel_x_obj, pyb_accel_x);
STATIC mp_obj_t pyb_accel_y(mp_obj_t self_in) {
return read_axis(MMA_REG_Y);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_accel_y_obj, pyb_accel_y);
STATIC mp_obj_t pyb_accel_z(mp_obj_t self_in) {
return read_axis(MMA_REG_Z);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_accel_z_obj, pyb_accel_z);
STATIC mp_obj_t pyb_accel_tilt(mp_obj_t self_in) {
uint8_t data[1];
HAL_I2C_Mem_Read(&I2cHandle_X, MMA_ADDR, MMA_REG_TILT, I2C_MEMADD_SIZE_8BIT, data, 1, 200);
return mp_obj_new_int(data[0]);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_accel_tilt_obj, pyb_accel_tilt);
STATIC mp_obj_t pyb_accel_filtered_xyz(mp_obj_t self_in) {
pyb_accel_obj_t *self = self_in;
memmove(self->buf, self->buf + NUM_AXIS, NUM_AXIS * (FILT_DEPTH - 1) * sizeof(int16_t));
uint8_t data[NUM_AXIS];
HAL_I2C_Mem_Read(&I2cHandle_X, MMA_ADDR, MMA_REG_X, I2C_MEMADD_SIZE_8BIT, data, NUM_AXIS, 200);
mp_obj_t tuple[NUM_AXIS];
for (int i = 0; i < NUM_AXIS; i++) {
self->buf[NUM_AXIS * (FILT_DEPTH - 1) + i] = MMA_AXIS_SIGNED_VALUE(data[i]);
int32_t val = 0;
for (int j = 0; j < FILT_DEPTH; j++) {
val += self->buf[i + NUM_AXIS * j];
}
tuple[i] = mp_obj_new_int(val);
}
return mp_obj_new_tuple(3, tuple);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_accel_filtered_xyz_obj, pyb_accel_filtered_xyz);
STATIC mp_obj_t pyb_accel_read(mp_obj_t self_in, mp_obj_t reg) {
uint8_t data[1];
HAL_I2C_Mem_Read(&I2cHandle_X, MMA_ADDR, mp_obj_get_int(reg), I2C_MEMADD_SIZE_8BIT, data, 1, 200);
return mp_obj_new_int(data[0]);
}
MP_DEFINE_CONST_FUN_OBJ_2(pyb_accel_read_obj, pyb_accel_read);
STATIC mp_obj_t pyb_accel_write(mp_obj_t self_in, mp_obj_t reg, mp_obj_t val) {
uint8_t data[1];
data[0] = mp_obj_get_int(val);
HAL_I2C_Mem_Write(&I2cHandle_X, MMA_ADDR, mp_obj_get_int(reg), I2C_MEMADD_SIZE_8BIT, data, 1, 200);
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_3(pyb_accel_write_obj, pyb_accel_write);
STATIC const mp_map_elem_t pyb_accel_locals_dict_table[] = {
{ MP_OBJ_NEW_QSTR(MP_QSTR_x), (mp_obj_t)&pyb_accel_x_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_y), (mp_obj_t)&pyb_accel_y_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_z), (mp_obj_t)&pyb_accel_z_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_tilt), (mp_obj_t)&pyb_accel_tilt_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_filtered_xyz), (mp_obj_t)&pyb_accel_filtered_xyz_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_read), (mp_obj_t)&pyb_accel_read_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_write), (mp_obj_t)&pyb_accel_write_obj },
};
STATIC MP_DEFINE_CONST_DICT(pyb_accel_locals_dict, pyb_accel_locals_dict_table);
const mp_obj_type_t pyb_accel_type = {
{ &mp_type_type },
.name = MP_QSTR_Accel,
.make_new = pyb_accel_make_new,
.locals_dict = (mp_obj_t)&pyb_accel_locals_dict,
};
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