usb host implementation status for esp32-s3

[josehdx]

Hello everyone

Wondering if i can get some assistance about the usb host (on the go) implementation using arduino core v3.0+

on the oficial Surface documentation we have this note:

"The ESP32-S2 and ESP32-S3 chips have native USB support, and MIDI over USB is supported by Control Surface when using version 3.0.0 or later of the arduino-esp32 core"

we are in v3.3.6 as far as i can tell

i would like to apply the example 4 found here for implementing a MIDI-over-USB to MIDI-over-BLE adapter on my MCU

i just did a copy paste of the code but is not working as it is. The usb host functionality and its technical notes from espressiff are making really hard to find if the capability has been completely set into arduino

For instance here , it is mentioned this: "it's being worked on. Current core 3.3.3 already supports TinyUSB host, but still needs Arduino abstraction for it."

They are talking about tinyusb. so i wonder if this is the backend use on this library, or if is an unrelated topic for this library example

I am aware that with my board, i need a usb-c breakout, which is currently connected to the right pins (D+, D- on pin 19 and 20 plus vbus for 5v and ground) and actually when the board is powered via battery or via usb on the serial port, the usb breakout can power ext devices as well, so the connections are fine.

So, if the surface Library should work with Arduino v3.0+ and if the connections are ok, is there anyway to troubleshoot this MIDI host functionality or is not tested yet with the curren library 2.1?

Thx!

[josehdx]

I found this related article but it was not concluded with a solution

I also found this on the guide regarding USBHostMIDI_Interface Class Reference but it is not mentioning esp32 boards, so i am not sure if it is mandatory to include such class for the example mentioned above

Thx again!

[tttapa]

Control Surface currently has no explicit support for USB Host on the ESP32. The main reason is that most Arduinos don't have proper software support for it, and things like enumeration of the connected devices and handling of USB events is much more involved than in the case of USB Device mode. That being said, if USB Host support is available in the arduino-esp32 core, you can easily integrate integrate it with a Control Surface MIDI_Interface using https://tttapa.github.io/Control-Surface/Doxygen/d7/d5f/Custom-USB-MIDI-Backend_8ino-example.html. You'll still have to manage all the USB Host-specific logic in your sketch (or offload it to another library like TinyUSB), though.

To clarify: if you have code in your sketch to configure the USB hardware in Host mode, handle enumeration, discover connected MIDI devices, set up the MIDI bulk endpoints for those devices, and handle other Host controller events, you can easily use the Control Surface example above to send and receive MIDI data over those endpoints. You could either use the Espressif USB Host library, see e.g. https://github.com/espressif/esp-idf/tree/master/examples/peripherals/usb/host/usb_host_lib or TinyUSB https://github.com/hathach/tinyusb/blob/master/examples/host/midi_rx/src/main.c. I have never tried this myself, though, and I am not up to date with the current status of TinyUSB Host support in the arduino-esp32 core. If TinyUSB works, that's probably the easiest route.

[josehdx]

thx for the detailed explanation :)

[tttapa]

I just had a look at the current status of USB Host support for the ESP32-S3 in TinyUSB, and it seems that it is not supported at all. So you'll have to use the lower-level Espressif APIs, unfortunately.

[josehdx]

This is weird

I found this and looks like is now supported? As i said before, its really hard for me to tell what is true or not regarding this host implementation. Anyway thanks for taking a look

[tttapa]

I was looking at https://components.espressif.com/components/espressif/tinyusb/versions/0.19.0~2/readme, which mentions

Only Device part of TinyUSB stack is supported. For Host mode, please refer to espressif/usb component.

And in the Adafruit TinyUSB Arduino library, the ESP32 configuration only enables USB Host support using an external USB Host shield:

https://github.com/adafruit/Adafruit_TinyUSB_Arduino/blob/3e5369cd4720c63d9caf31db6ca4c18ce7bcd0b7/src/arduino/ports/esp32/tusb_config_esp32.h#L144-L146

OTOH, there's threads like this one: hathach/tinyusb#2634
The author claims that USB Host is supported, but it is unclear to me whether it is actually usable in the Arduino framework.

[josehdx]

Thx again!

[LsrSal]

OP,
I successfully made USB host adapter for my Roland FP10 (and tested with bunch of other gear) using this library. I believe (I did not try), it can coexist with ControlSurface library, though not sure if you can use pipes in between.

It uses tinyUSB stack, so I would expect it to run on any micro that supports it, and also support host function. I made my hardware on RPi2040Zero.
I did not use any adapters or breakouts for USB. UCB-C already on board with proper adapters goes right into peripheral midi device. I had to provide power for RPi2040 board through separate pins. It works solid, with BOM cost below $10, much cheaper than anything with MIDI-USB-host function available on Amazon.

[josehdx]

could you share your code? i would like to implement the library and also to take a look how you did pipes or related stuff. thx

[LsrSal]

Note that for my hardware implementation of USB host adapter I use RP2040_zero. I believe it should also compile for ESP32-S2 or S3, though I would suggest to use original example code from original library as staring point and edit it for LED you have onboard. Or edit it out for that matter.
For your convenience compiled file also included. Note that I use IOs 4 and 5 for TX and RX (Alternative pins for hardware COM2).

https://github.com/LsrSal/ZERO_USB_MIDI_HOST

[josehdx]

I believe in the end.the issue was that my board was not fully providing 5v to the usb breakout cause the code works as intended with another usb midi powered by internal battery. So i would recommend to try that way ot buy a power booster to 5v