# Motors

![](https://img.bricklink.com/ItemImage/PL/6181852.png)

## Controlling Motors

Methods to activate motors are:
- `start_speed(speed_primary, speed_secondary)` - enables motor with specified speed forever 
- `timed(time, speed_primary, speed_secondary)` - enables motor with specified speed for `time` seconds, float values accepted
- `angled(angle, speed_primary, speed_secondary)` - makes motor to rotate to specified angle, `angle` value is integer degrees, can be negative and can be more than 360 for several rounds
- `stop()` - stops motor

Parameter `speed_secondary` is used when it is motor group of `motor_AB` running together. By default, `speed_secondary` equals `speed_primary`. 

Speed values range is `-1.0` to `1.0`, float values. _Note: In group angled mode, total rotation angle is distributed across 2 motors according to motor speeds ratio, see official doc [here](https://lego.github.io/lego-ble-wireless-protocol-docs/index.html#tacho-math)._

An example:
```python
from pylgbst.hub import MoveHub
import time

hub = MoveHub()

hub.motor_A.timed(0.5, 0.8)
hub.motor_A.timed(0.5, -0.8)

hub.motor_B.angled(90, 0.8)
hub.motor_B.angled(-90, 0.8)

hub.motor_AB.timed(1.5, 0.8, -0.8)
hub.motor_AB.angled(90, 0.8, -0.8)

hub.motor_external.start_speed(0.2)
time.sleep(2)
hub.motor_external.stop()
```


## Motor Rotation Sensors

Any motor allows to subscribe to its rotation sensor. Two sensor modes are available: rotation angle (`EncodedMotor.SENSOR_ANGLE`) and rotation speed (`EncodedMotor.SENSOR_SPEED`). Example: 

```python
from pylgbst.hub import MoveHub, EncodedMotor
import time

def callback(angle):
    print("Angle: %s" % angle)

hub = MoveHub()

hub.motor_A.subscribe(callback, mode=EncodedMotor.SENSOR_ANGLE)
time.sleep(60) # rotate motor A
hub.motor_A.unsubscribe(callback)
```