# Microhard USB Carrier Board Questions

Source: https://forum.modalai.com/topic/2769/microhard-usb-carrier-board-questions
Category: General Questions (https://forum.modalai.com/category/2/general-questions)
Posted: 2023-10-24 21:43:39 UTC by JSchinowsky
Replies: 1 · Views: 358

## JSchinowsky · 2023-10-24 21:43:39 UTC

Hello,
I am trying to setup and use a Microhard USB Carrier Board and I had two questions. 
- What are the peripheral USB ports used for? how are they different from the 7 pin USB port on the bottom of the board?
- What are is the pinout for the 7 pin and 4 pin USB ports
Best,
Jonathan

## Reply by tom (ModalAI staff) · 2023-10-24 21:52:37 UTC

@JSchinowsky These should help you out:

voxl add-on: https://docs.modalai.com/microhard-add-on-datasheet/#board-connections-and-io
standalone: https://docs.modalai.com/microhard-usb-carrier/#board-connections-and-io