148 lines
3.6 KiB
Go
148 lines
3.6 KiB
Go
package i2c
|
|
|
|
import (
|
|
"bytes"
|
|
"encoding/binary"
|
|
"time"
|
|
|
|
"github.com/hybridgroup/gobot"
|
|
)
|
|
|
|
var _ gobot.Driver = (*MPU6050Driver)(nil)
|
|
|
|
const mpu6050Address = 0x68
|
|
|
|
const MPU6050_RA_ACCEL_XOUT_H = 0x3B
|
|
const MPU6050_RA_PWR_MGMT_1 = 0x6B
|
|
const MPU6050_PWR1_CLKSEL_BIT = 2
|
|
const MPU6050_PWR1_CLKSEL_LENGTH = 3
|
|
const MPU6050_CLOCK_PLL_XGYRO = 0x01
|
|
const MPU6050_GYRO_FS_250 = 0x00
|
|
const MPU6050_RA_GYRO_CONFIG = 0x1B
|
|
const MPU6050_GCONFIG_FS_SEL_LENGTH = 2
|
|
const MPU6050_GCONFIG_FS_SEL_BIT = 4
|
|
const MPU6050_RA_ACCEL_CONFIG = 0x1C
|
|
const MPU6050_ACONFIG_AFS_SEL_BIT = 4
|
|
const MPU6050_ACONFIG_AFS_SEL_LENGTH = 2
|
|
const MPU6050_ACCEL_FS_2 = 0x00
|
|
const MPU6050_PWR1_SLEEP_BIT = 6
|
|
const MPU6050_PWR1_ENABLE_BIT = 0
|
|
|
|
type ThreeDData struct {
|
|
X int16
|
|
Y int16
|
|
Z int16
|
|
}
|
|
|
|
type MPU6050Driver struct {
|
|
name string
|
|
connection I2c
|
|
interval time.Duration
|
|
Accelerometer ThreeDData
|
|
Gyroscope ThreeDData
|
|
Temperature int16
|
|
gobot.Eventer
|
|
}
|
|
|
|
// NewMPU6050Driver creates a new driver with specified i2c interface
|
|
func NewMPU6050Driver(a I2c, v ...time.Duration) *MPU6050Driver {
|
|
m := &MPU6050Driver{
|
|
name: "MPU6050",
|
|
connection: a,
|
|
interval: 10 * time.Millisecond,
|
|
Eventer: gobot.NewEventer(),
|
|
}
|
|
|
|
if len(v) > 0 {
|
|
m.interval = v[0]
|
|
}
|
|
|
|
m.AddEvent(Error)
|
|
return m
|
|
}
|
|
|
|
func (h *MPU6050Driver) Name() string { return h.name }
|
|
func (h *MPU6050Driver) SetName(n string) { h.name = n }
|
|
func (h *MPU6050Driver) Connection() gobot.Connection { return h.connection.(gobot.Connection) }
|
|
|
|
// Start writes initialization bytes and reads from adaptor
|
|
// using specified interval to accelerometer andtemperature data
|
|
func (h *MPU6050Driver) Start() (err error) {
|
|
if err := h.initialize(); err != nil {
|
|
return err
|
|
}
|
|
|
|
go func() {
|
|
for {
|
|
if err := h.connection.I2cWrite(mpu6050Address, []byte{MPU6050_RA_ACCEL_XOUT_H}); err != nil {
|
|
h.Publish(h.Event(Error), err)
|
|
continue
|
|
}
|
|
|
|
ret, err := h.connection.I2cRead(mpu6050Address, 14)
|
|
if err != nil {
|
|
h.Publish(h.Event(Error), err)
|
|
continue
|
|
}
|
|
buf := bytes.NewBuffer(ret)
|
|
binary.Read(buf, binary.BigEndian, &h.Accelerometer)
|
|
binary.Read(buf, binary.BigEndian, &h.Temperature)
|
|
binary.Read(buf, binary.BigEndian, &h.Gyroscope)
|
|
h.convertToCelsius()
|
|
time.Sleep(h.interval)
|
|
}
|
|
}()
|
|
return
|
|
}
|
|
|
|
// Halt returns true if devices is halted successfully
|
|
func (h *MPU6050Driver) Halt() (err error) { return }
|
|
|
|
func (h *MPU6050Driver) initialize() (err error) {
|
|
if err = h.connection.I2cStart(mpu6050Address); err != nil {
|
|
return
|
|
}
|
|
|
|
// setClockSource
|
|
if err = h.connection.I2cWrite(mpu6050Address, []byte{MPU6050_RA_PWR_MGMT_1,
|
|
MPU6050_PWR1_CLKSEL_BIT,
|
|
MPU6050_PWR1_CLKSEL_LENGTH,
|
|
MPU6050_CLOCK_PLL_XGYRO}); err != nil {
|
|
return
|
|
}
|
|
|
|
// setFullScaleGyroRange
|
|
if err = h.connection.I2cWrite(mpu6050Address, []byte{MPU6050_RA_GYRO_CONFIG,
|
|
MPU6050_GCONFIG_FS_SEL_BIT,
|
|
MPU6050_GCONFIG_FS_SEL_LENGTH,
|
|
MPU6050_GYRO_FS_250}); err != nil {
|
|
return
|
|
}
|
|
|
|
// setFullScaleAccelRange
|
|
if err = h.connection.I2cWrite(mpu6050Address, []byte{MPU6050_RA_ACCEL_CONFIG,
|
|
MPU6050_ACONFIG_AFS_SEL_BIT,
|
|
MPU6050_ACONFIG_AFS_SEL_LENGTH,
|
|
MPU6050_ACCEL_FS_2}); err != nil {
|
|
return
|
|
}
|
|
|
|
// setSleepEnabled
|
|
if err = h.connection.I2cWrite(mpu6050Address, []byte{MPU6050_RA_PWR_MGMT_1,
|
|
MPU6050_PWR1_ENABLE_BIT,
|
|
0}); err != nil {
|
|
return
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// The temperature sensor is -40 to +85 degrees Celsius.
|
|
// It is a signed integer.
|
|
// According to the datasheet:
|
|
// 340 per degrees Celsius, -512 at 35 degrees.
|
|
// At 0 degrees: -512 - (340 * 35) = -12412
|
|
func (h *MPU6050Driver) convertToCelsius() {
|
|
h.Temperature = (h.Temperature + 12412) / 340
|
|
}
|