QUERY · ISSUE

USB HID keyboard and mouse at the same time

openby aloneguidopened 2024-09-09updated 2025-06-15

Does anyone know how to create a USB device that acts as a mouse and keyboard at the same time? Examples here https://github.com/micropython/micropython-lib/tree/fbf7e120c6830d8d04097309e715bcab63dcca67/micropython/usb/examples/device are excellent, but I can only manage to work exclusively as a mouse or a keyboard, but not both at the same time.

As long as I understand, I need to prepare a report descriptor in a special way, but I'm not a HID expect and not sure how to do it. Please share if you have done it before ;)

3 comments

dov · 2025-06-11

Before finding this issue, I just asked the same question in micopython discussions:

https://github.com/orgs/micropython/discussions/17475

I also copied my question into github copilot and the response that I got was more or less "it is currently not supported", and it offered to help writing a combined mouse and keyboard hid module.

aloneguid · 2025-06-13

It's beeen a while! Since then I have done it multiple times. It is possible, but you will have to write your own device rather than use KeyboardInterface and MouseInterface. It's not possible to run two at the same time, because those would be two separate physical devices, so you would need two physical USB ports, which is also not supported. I should write a blog post, just didn't get to it.

In general, I had to write my own device anyway, because I wanted to add support for extra mouse button and a wheel, which is not part of MouseInterface. Currently I have a device which works as a keyboard, mouse, joystick and consumer control at the same time. I'll try to detail this next week.

A bit off topic regarding the discussion - I was trying to do the same a while ago - wireless control via wifi or bluetooth. I settled on bluetooth at the end, because it can work "offline". But I found that even keyboard support wirelessly is a bit of a challenge with MicroPython due to performance issues. There is a lot of code regarding throttling and aggregating keyboard events to make keyboard type close to a normal bluetooth keyboard. Moving a mouse wirelessly is not possible at all due to massive latency issues. Good luck though! A bit more offtopic - I ended up rewriting it in C and pico SDK after hitting many more restrictions with USB and Bluetooth and it's been literally 100 times lower latency. Still struggling with buttery smooth mouse movement but it's getting very close. No issues with keyboard control, I can even do gaming over bluetooth comfortably.

dov · 2025-06-15

Hi @aloneguid . Thanks for your reply. I'd love to get a copy of your combined keyboard and mouse usb driver! Was it in pure python, or did you need to change the micropython C-Code?

Regarding latency, I'm aware that it is going to be bad, but I'd still like to experience it on my own. I did a simple ping latency of a web sockets server running on the MCU, and it was between 6-300ms. The worst case is clearly unacceptable, but it happened only occasionally.

In any case my idea was to be able to remote control another computer by, and since it is not going to be continuously, perhaps the latency isn't too annoying.

CANDIDATE · ISSUE

Support for USB_HID Consumer Control devices?

closedby klardotshopened 2018-09-24updated 2018-10-03

For context in case any of y'all aren't HID folks (I wasn't until recently!), Consumer Mode is an additional (pseudo-)device a USB peripheral can advertise to allow a whole bunch of generally media-related functionalities - notably, the "media keys" of modern keyboards (PlayPause, VolumeUp, VolumeDown, that goofy button that launches your default web browser when you probably meant to hit some other key, etc).

I see some vague references to consumer device reports in the STM32 USB HAL code (I'm testing primarily on a PyBoard, though NRF devices are also in my scope of interest), but nothing notable exposed to Python. I suppose I could use a custom tuple as the hid argument to USB_HID('VSC+HID', hid=...), but as far as I understand it, I'd then lose the main keyboard HID device.

I suppose a related question here is how to "be" two HID types at once in MicroPython - let's say for example I wanted to throw a trackpoint and some mouse buttons onto a MicroPython-based keyboard. I'd need to "be" at least two HID types here - keyboard and mouse. Three if I want volume keys on said device - keyboard, mouse, and consumer control.

There's some existing art in this general realm, particularly on NRF chips, over in https://github.com/adafruit/circuitpython land (see also), but at this point that project has deviated far enough that I'm nowhere near comfortable enough with C to try to backport their additions.

I'm hoping I'll be told I need to read more closely, and that Consumer Control devices are supported, but from my understanding so far, it looks like there's just basic stubs in C, and no way for me to (easily, out-of-the-box) use them. Thanks folks!