5.1.1. Configuring a Limit or Kill Switch
Limit switches and kill switches help protect your motor controller from performing unwanted actions. For example, analog limit switches could be configured to prevent your actuator from moving out of its valid range. An RC kill switch could be configured to conveniently immobilize an autonomous robot from a distance using an RC Transmitter and Receiver.
To configure your Simple Motor Controller to use a limit or kill switch, follow these steps:
- Decide what channel you are going to connect your limit switch to, and connect it to that channel as described in Section 4.3 if it is an RC limit or kill switch or Section 4.4 if it is an analog limit or kill switch.
- If you are using an Analog channel for your limit switch and you decide to use the internal pull-up instead of supplying an external one, check the “Enable pull-up resistor” box for that channel in the Input Settings tab.
- If you are using an Analog channel and have chosen a wiring configuration that makes it impossible for the controller to detect when your switch is disconnected, check “Ignore pot disconnect” box in the Advanced Settings. Disconnect detection works by toggling power to the analog power pins (+) and making sure that this toggling has an effect on the voltage on the sigal pin (A1 or A2). If you have wired your switch such that the analog power pin is not connected to the signal pin, you will need to do this.
- Select the desired Alternate Use for the limit switch channel. This determines whether it will be a Forward Limit Switch, Reverse Limit Switch, or Kill Switch. See Section 5.1 for details about the Alternate Use.
- Click “Apply Settings”.
- Look at the current channel value label in the Input Settings tab. Press or activate your switch and make sure that the channel value changes significantly. If the value does not change, then you should double check your connections and settings and try again.
- Click the “Learn…” button for the channel in the Input Settings tab. The Channel Setup Wizard will walk you through the steps needed to calibrate your limit switch’s scaling parameters.