# Legacy - [VEX Cortex](https://wiki.purduesigbots.com/vex-electronics/legacy/vex-cortex.md): The VEX Cortex is the older microcontroller that was used in VRC and VEXU - [Power Expander](https://wiki.purduesigbots.com/vex-electronics/legacy/power-expander.md): A VEX Power Expander is a device which allows up to four of the VEX Motors on a robot to run from a second VEX Battery while still under the control of the VEX Cortex or VEX PIC. - [VEX Motor Controller](https://wiki.purduesigbots.com/vex-electronics/legacy/motor-controller.md): The VEX Motor Controller is a device which converts a standard logic-level PWM servo control signal into motive power to drive a Motors. - [VEX Cortex Wiring Guide](https://wiki.purduesigbots.com/vex-electronics/legacy/legacy-wiring-guide.md): This guide provides general wiring tips for the legacy cortex system. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://wiki.purduesigbots.com/vex-electronics/legacy.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.