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Thread: Tall-Dog Teensy 4.0 Breakout Board Questions

  1. #1

    Tall-Dog Teensy 4.0 Breakout Board Questions

    I bought a Tall-Dog Breakout Board for the Teensy 4.0, to replace the smoked Teensy 3.5 I have.

    This time I bought it assembled. All I had to do was install the header pins for the I/O I need.

    This will be installed in a box with a panel mounted USB port. As I am using an external (to the Teensy) power supply I do not need the USB supplied power.

    I hooked up the D+ and D- (and ground) pins on the Breakout Board to the panel mounted USB jack and nothing happens. But if I use the micro USB port on the Teensy 4.0 itself, everything works as it should. I can load a modified (faster blink rate) blink sketch and it works.

    Anyone here know how I can get the D+ and D-pins to work?

    How should the switches on the Breakout Board be set? In the far distant future this will be exchanging data and commands with a laptop, but for now it will be used just for uploading the sketch.

    There is a button on the Breakout Board that doesn't seem to do anything. What is it for?

    I do not see any user information on the Tall-Dog website.

  2. #2
    Senior Member+ defragster's Avatar
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    D+ and D- are just the data signals FOR USB HOST on the T4.0.

    To complete Host the GND and USB 5V power pins on the connector also need to be brought out. But those pins are NOT duplicates of the Device USB.

    To extend the Device USB only the soldered onboard connector works on T_4.0 - there are extension cables to mate and extend that.

  3. #3
    Quote Originally Posted by defragster View Post
    D+ and D- are just the data signals FOR USB HOST on the T4.0.

    To complete Host the GND and USB 5V power pins on the connector also need to be brought out. But those pins are NOT duplicates of the Device USB.

    To extend the Device USB only the soldered onboard connector works on T_4.0 - there are extension cables to mate and extend that.
    Thank you, defragster.

    I was just now looking at the Teensy 4.0 pinout card, and it was beginning to dawn on me that that may be the case. I could cannibalize a micro USB cable to make the connections .

  4. #4
    Aha!!! Now that is interesting!

    I cannibalized a micro USB cable, and looked up the color coding scheme of the wires before soldering it to the panel mounted connector.

    Positive white wire to D+, and Negative green wire to D-, right?

    Wrong! Green wire goes to D+ and White wire goes to D-. Either that,or the panel mount connector I have is labeled wrong. Forgot where I got it so I can't complain, but if anyone else goes down the same road keep this in mind.

    I wonder if that was the problem with the Teensy 3.5 I first tried, since I had wired Teensy D+ to connector D+, and likewise D- to D-?

    Now, onwards and upwards!

  5. #5
    Senior Member+ defragster's Avatar
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    That color code seems to be the expected standard:
    Click image for larger version. 

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    Glad that got you progress.

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