# Equipping a microservo with Crocodile clips ## ~ hint If you are running a class or activity, you should consider preparing all servos before hand. ## ~ ## Using a microservo with the @boardname@ The @boardname@ provides just enough current to operate the SG90 microservo. The servo requires 3 connections: GND, 3V and a logic pin. In this tutorial, we will equip the servo with crocodile clips to make it easier to use. However, you could also use a shield or female to crocodile clips to acheive the same effect. ## The easy way: Alligator/Crocobile Clip to Male Jumpers #hintconnection The easiest way to connect a servo to the @boardname@ is to use cables that have an **Alligator/Crocobile clip** on one end and a **Male jumper (pig tail)** on the other end. You can purchase bundles of such cables from various electronic resellers or easily build yours as show below. https://youtu.be/XtzsydSTXEg ## Materials * 1 Crocodile clip cable * 1 male (pig tail) cable * Cutting pliers or wire cutter * 1 shrink wrap cables and a lighter Simple cut the cables, strip them, thread the cables together and cover with the shrink wrap. ## ~ hint It is very **important** to ensure that there is a good connection between the 2 cables. If the connection is weak, the microservo will not receive enough current and it will not work. **If you have access to a soldering iron, we strongly recommend to solder this connection.** ## ~ ## Direct connection You can also connect your crocodile clips directly to the servo. ## Materials * Cutting pliers or wire cutter * Tape (masking, duct tape, and/or packing tape) * 3 crocodile clips, yellow, red and black. * 1 micro servo 9g (SG90) ## Step 1: cutout the connector Using the cutting pliers, cut out the dark plastic connector.  ## Step 2: strip out cables Using the plier or a wire stripper, strip the plastic from the cables.  ## Step 3: threading the servo cablers Thread the servo cables.  ## Step 4: crocobile clip Cut a crocodile cable in two and strip out the casing. If possible try to use the same cable colors as the servo!  ## Step 5: thread cables together Place the cables next to each other  ... and thread them together.  ## ~ hint It is very **important** to ensure that there is a good connection between the 2 cables. If the connection is weak, the microservo will not receive enough current and it will not work. **If you have access to a soldering iron, we strongly recommend to solder this connection.** ## ~ ## Step 4: protect the connection Protect the connection with shrinkwrap tubes, electrical or duct tape.  ## Step 5: repeat for all cables Repeat the same process until all cables are connected.  ## Step 6: testing! It's time to test that your connection are all proper and that the servo will function **when the @boardname@ is powered by battery**. * Connect the microservo to the @boardname@. Black cable on ``GND``, red cable on ``3V`` and remaining cable on ``P0``.  ## ~ hint When attaching the crocodile clips to the pins, don't hesitate to grab the side of the board with the jaws.  ## ~ * Download the following code to your @boardname@ ```blocks basic.forever(() => { pins.servoWritePin(AnalogPin.P0, pins.map( input.acceleration(Dimension.X), -512, 512, 0, 180 )) }) ``` * When powered by USB, make sure that the servo moves when you tilt the board. * When powered by batteries **only**, make sure that the servo moves when you tilt the board. ## Calibrating Using the [servo calibrator program](/examples/servo-calibrator) to determine the best angles to use in your make. ## Troubleshooting If your servo seems to sutter and stay stuck at a particular position, it means that it is not receiving enough power. This is probably due to a weak connection or low battery level. Check each connection and check your batteries.