# VOXL as usb2 host not working via j8

Source: https://forum.modalai.com/topic/540/voxl-as-usb2-host-not-working-via-j8
Category: Flight Core and Legacy VOXL (https://forum.modalai.com/category/9/flight-core-and-legacy-voxl)
Tags: voxl
Posted: 2021-11-03 09:37:23 UTC by Nirge
Replies: 2 · Views: 826

## Nirge · 2021-11-03 09:37:23 UTC

Hi, 
Connecting my laptop to voxl via adb works on j8 connecter.
However, an STM based device is not recognized when connecting a client device to voxl using micro-usb to micro-usb cable.
The same device is recognized when connecting via the usb expander (https://docs.modalai.com/usb-expander-and-debug-datasheet/)
```/ # lsusb
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 002: ID 0483:5740 STMicroelectronics STM32F407
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
```
https://docs.modalai.com/voxl-as-usb-host/ does not specify any special requirements. 
Am I missing something? is the micro-usb cable needs to be an OTG cable with ID pin?
Best regards,
Nir

## Reply by modaltb (ModalAI staff) · 2021-11-04 00:27:58 UTC

Hi @Nirge ,

A standard cable won't work.

Some info here: 
https://docs.modalai.com/voxl-datasheets-connectors/#notes-3

From here: https://docs.modalai.com/voxl-as-usb-host/#background

```text
Because the USB3.0 SS pins on the VOXL (Snapdragon 821) cannot support TX/RX swapping, they were set to peripheral mode since the 821 is used mainly in phones and peripheral mode is way more commonly used in a phone configuration.

In order for systems to use the standard micro-b to type A female OTG cables, they need to do TX/RX swapping.

Since VOXL can't do this, it needs to use a non-standard pinout as its default configuration is peripheral mode in order to get the SS.
```

## Reply by Nirge · 2021-11-11 09:50:41 UTC (in reply to modaltb)

@modaltb Using USB 2.
Got my hands on an OTG adapter, seems to be doing the trick.