3.14 Servo
3.14.1 Overview
The 9g servo features small size but high performance and precision and is with good torque and accuracy, so it is perfect for small machines. With up to 180 degrees rotation angle, it enables extremely precise rotation and control and can be started fast with low noise.
3.14.2 Schematic Diagram
Angle range: 180°(there are 360°, 180° and 90°)
Drive voltage: 3.3V / 5V
Usually three wires:
GND: grounded, in brown
VCC: connect to +5v (3.3V) power, in red
S: signal pin to control PWM signal, in orange
Control principle: The rotation Angle of the servo is controlled by adjusting the duty cycle of the PWM (pulse width modulation) signals. Theoretically, the period of the standard PWM signal is fixed at 20ms (50Hz), so the pulse width should be 1ms ~ 2ms. But in fact, it is 0.5ms ~ 2.5ms, corresponding to the servo angle of 0° ~ 180°. Note that the angle for the same signal varies from servo brands.
3.14.3 Code Blocks
Blocks in 
:
is a block included in coding box library. It controls the rotation angle of the servo in the coding box.
3.14.4 Test Code
You can manually build blocks, or directly open the code file we provide: 3-14-Servo.ubp. If you have any questions about how to open code files or upload code, please back to 1.9 Upload Code.
Build code blocks:
In
, drag 
and 
to the script area, and stack them together.
In
, drag block and put it into . Modify the angle to 0 degree.
In
, drag 
block and set to 1000, and put it under
.
Duplicate all
but set degree to 90.Duplicate all
again but set degree to 180.
Complete code:
3.14.5 Test Result
Connect the coding box to the MicroBlocks via USB or Bluetooth, and click 
to upload the code to the coding box. The servo rotates to 0 degrees ans stays for 2 seconds (If its initial angle is 0, it will not rotate), and then it rotates to 90 degrees and stays for 2 seconds. At last, it turns to 180 degrees and stays for 2 seconds. These actions repeat.