mpu6050: add driver

Only the accelerometer is supported at the moment.

mpu6050/mpu6050.go

@@ -0,0 +1,48 @@
+// Package mpu6050 provides a driver for the MPU6050 accelerometer and gyroscope
+// made by InvenSense.
+//
+// Datasheets:
+// https://store.invensense.com/datasheets/invensense/MPU-6050_DataSheet_V3%204.pdf
+// https://www.invensense.com/wp-content/uploads/2015/02/MPU-6000-Register-Map1.pdf
+package mpu6050
+
+import (
+	"machine"
+)
+
+// Device wraps an I2C connection to a MPU6050 device.
+type Device struct {
+	bus machine.I2C
+}
+
+// NewI2C creates a new MPU6050 connection. The I2C bus must already be
+// configured.
+//
+// This function only creates the Device object, it does not touch the device.
+func NewI2C(bus machine.I2C) Device {
+	return Device{bus}
+}
+
+// Connected returns whether a MPU6050 has been found.
+// It does a "who am I" request and checks the response.
+func (d Device) Connected() bool {
+	data := []byte{0}
+	d.bus.ReadRegister(Address, WHO_AM_I, data)
+	return data[0] == 0x68
+}
+
+// Configure sets up the device for communication.
+func (d Device) Configure() {
+	d.bus.WriteRegister(Address, PWR_MGMT_1, []uint8{0})
+}
+
+// ReadAcceleration reads the current acceleration from the device and returns
+// it.
+func (d Device) ReadAcceleration() (x int16, y int16, z int16) {
+	data := make([]byte, 6)
+	d.bus.ReadRegister(Address, ACCEL_XOUT_H, data)
+	x = int16((uint16(data[0]) << 8) | uint16(data[1]))
+	y = int16((uint16(data[2]) << 8) | uint16(data[3]))
+	z = int16((uint16(data[4]) << 8) | uint16(data[5]))
+	return
+}