Teensy 4.0/4.1, USB Type option "No USB" not present?

PaulS

Well-known member
In the Arduino IDE, for Teensy 3.1/3.2 there is a USB Type option "No USB". For the newer Teensy 4.0/4.1 there is not.

NoUSB.png

RawHID.png

I searched this forum ofcourse but it would not let me search on "No USB" specifically. It's probably discussed somewhere in the long Teensy-4-0-First-Beta-Test thread...
I recall reading an answer from Paul on deleting the "All of the above" option, but I don't recall reading on the "No USB" option.

Does anyone of you know about removing the "No USB' option? And why?

Related question: is the "RawHID" option identical to the "No USB" option?

Running Arduino 1.8.12, Teensyduino 1.52, Windows 7.

Thanks,
Paul
 
I am not sure how well the support for No USB is implemented (or not).

But if you look in the boards.txt file you will see lines like:
Code:
#teensy40.menu.usb.disable=No USB
#teensy40.menu.usb.disable.build.usbtype=USB_DISABLED
Which shows they are commented out.

Have no idea what would happen if you un-comment them.

I do see a few places in the Teensy4 sources that check for USB_DISABLED
 
Thanks Kurt.
I guess Paul must have had a good reason to uncomment the "No USB" option.
On my related question: "No USB" really means no USB, not even a HID device. I checked on a T3.2. When active as a "No USB" device, you have to push the program button on the Teensy to get it reprogrammed. The Teensy Loader won't program automatically.

Addition: it looks like a fresh Teensy 4.1 arrives from the factory as a RawHID device.

Paul
 
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IIRC - T_4.0 beta started without No_USB by design to assure the 480Mbps stack was tested and working to build the other USB types.

Uncommenting that may be low priority - or perhaps a reason?
 
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