Bluetooth support for Teensy 4.1, hardware and software


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I've been using the Teensy 4.0 series and am considering the Teensy 4.1 series. I am confused about whether Bluetooth or other wireless devices are shipped with the 4.1. On Amazon ("Teensy 4.1 (Without Pins)", there is mention of the Teensy 4.1 and 2.4 GHz wireless, but I don't see it on the spec sheet. A search for "Bluetooth 4.1" was inconclusive, and I couldn't search the thread "Teensy 4.1 Beta Test" well enough to find mention of the phrase. I don't need Bluetooth for the application, but I do need to know if it's there for spectrum compliance documentation.

My question: Does the Teensy 4.1 have the Bluetooth hardware as shipped, and if so, where can I find more details?

If the Bluetooth is an add-on capability (shield, etc.) but not present as shipped, that would also be good to know.

The Teensy 4.1 like others ship as just a the Teensy and do not have any onboard radio.

Like the T_3.6 the T_4.1 has USBHost port pins on the board and they share the same secondary USB host processor interface. { also found as pads on the T_4.0 }

So the same software and hardware capabilities apply. There is a USBHost thread for T_3.6 that shows the USB Bluetooth adapters tested to work with the USBHost library.

To add Bluetooth to Teensy takes an add on device - and the T_4.1 can do that with some USB Bluetooth 'dongles'
The current generation of Teensys do not support bluetooth directly. However, the company ( that makes the chips inside of the Teensy (i.MXRT 1062 for Teensy 4.0/4.1) did recently acquire a bluetooth and wifi chipset maker, so it is possible that a future generation of Teensy will include it:

I believe there are 3 main ways to add bluetooth support:
  • Using USB Host support that defragster mentioned on the Teensy 3.6, 4.0, and 4.1. Note, the 3.6 and 4.1 are easier to add external USB host support, but for the 4.0, you can access the USB HOST pins by soldering pads underneath the Teensy;
  • Using a bluetooth device that communicates via a serial line (Serial1, Serial2, etc.); (and)
  • Using a bluetooth device that communicates via the SPI protocol.
Perfect - thank you for the quick response. Mark

Glad that helped. @MichaelM noted the other typical means of getting bluetooth. Focused on the USBHost assuming that software interface was that conflated with 'direct' Bluetooth support.

This is a long 31 page thread covering the latest evolution of :: T3-6-USB-Host-Bluetooth - where as noted the T_4.x hardware works the same as the T_3.6.
Hi all. I am working on a project with a Teensy 4.1 board and using a Mac computer. I am sending data with the serial cable at the moment using ( this library: MIDIUSB) to be able to send MIDI data.

It works fine with the cable. I am looking forward to send the data wirelessly. I've looked for "bluetooth dongles" on amazon without much luck. Mostly I found bluetooth receivers for Windows computers. Or devices apparently made specifically for audio

Could anyone point to some device like what I am looking for? Of course any other alternatives are welcome.

By "Using a bluetooth device that communicates via a serial line (Serial1, Serial2, etc.)" you mean something like this Would a module like this one work?