Announcement

Collapse
No announcement yet.

CarPc Joycon Exd USB power?

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • CarPc Joycon Exd USB power?

    Does the Exd supply power on the USB port?

    I'm looking at driving my Android phone from the steering wheel control, via an Exd.

    But if the phone is connected to the Exd by USB, I can't power the phone.

    Does the Exd supply power on the USB port when the Exd has external power?

    If not, I guess I need a USB hub. Any recommendations?

  • #2
    it definitely wont power the phone, the phone will power the Joycon. The Joycon RECEIVES power via USB.
    mp3Car.com Senior Tech Blogger (Want a product reviewed? Contact me.)
    Follow Me on Twitter or Facebook
    Live mp3Car Facebook Chat

    Comment


    • #3
      That's a shame - it makes using an Android phone with the Joycon pretty much a non-starter for me.

      I use my phone with Google Maps for navigation, and Play Music for sounds. To run Google Maps (drawing power for GPS and screen permanently on) requires permanent power in excess of the 500mA that a USB hub would provide.

      If the only way to connect the phone to the Joycon is via USB, then this clearly won't work as the phone won't be able to charge.

      Comment


      • #4
        Originally posted by gooman View Post
        That's a shame - it makes using an Android phone with the Joycon pretty much a non-starter for me.

        I use my phone with Google Maps for navigation, and Play Music for sounds. To run Google Maps (drawing power for GPS and screen permanently on) requires permanent power in excess of the 500mA that a USB hub would provide.

        If the only way to connect the phone to the Joycon is via USB, then this clearly won't work as the phone won't be able to charge.
        Well it seems all you'd need is a self powered USB hub like this one to power the joycon and charge the phone at the same time.
        mp3Car.com Senior Tech Blogger (Want a product reviewed? Contact me.)
        Follow Me on Twitter or Facebook
        Live mp3Car Facebook Chat

        Comment


        • #5
          Like any USB powered hub, it only provides 500mA.

          The phone needs at least 750mA when running GPS and permanently-on screen, otherwise the battery drains. It's not possible to have the phone connected to the Joycon via USB adn be properly powered at the same time.

          This is an HTC One X - my previous Samsung Galaxy S II was the same. I'd guess most smartphones will fall into the same trap.

          Comment


          • #6
            You can actually get away with just connecting the D+ and D- wires to your phone, and get the 5V and ground from elsewhere and it will work. I would recommend at least connecting the ground too though.

            I have done all kinds of USB experiments, including running a 12 to 5 DC-DC converter to power my USB ODAC on the outer two red and black wires, then connecting the green and white only to the motherboard. It works just fine.

            Comment


            • #7
              rray: You HAVE to share the ground some how. Otherwise you can cause damage to the equipment. Not sure how yours is working without sharing the ground...

              To power port just use the black and red wires...

              To send/receive data just use black, green and white wires...

              Not using the black wire can cause voltage differences that can damage your devices. Your's must be grounded through case grounds or something which is why they are working.. But still not a good idea.



              Rodney

              Comment


              • #8
                This still isn't going to work for my application.

                For a phone to know that it can try to draw more than 500mA, the data pins have to shorted together on the phone side of the connection.

                So I can either have the phone able to draw enough power, or I can connect it to the Joycon - not both.

                Without a Bluetooth connection, its simply not going to be viable to connect an Android phone used for navigation to a Joycon Exd.

                Comment


                • #9
                  Mine does have the ground shared, because all the grounds in my car are shared. So the ODAC's converter ground is connected to the MOBO's converter's ground. I have both battery grounds paralleled, and all electronics grounded to those.

                  In the case of the phone to Joycon, that is why I mentioned ground should probably be connected too, as it's always good practice to ground everything; but the +5V does not need to be connected to the phone, only to the Joycon.

                  The point being he can power the Joycon from elsewhere and just use the phone's D+ and D- for the USB communication, and of course share a ground to the phone.

                  Comment


                  • #10
                    Originally posted by rray View Post
                    Mine does have the ground shared, because all the grounds in my car are shared. So the ODAC's converter ground is connected to the MOBO's converter's ground. I have both battery grounds paralleled, and all electronics grounded to those.

                    In the case of the phone to Joycon, that is why I mentioned ground should probably be connected too, as it's always good practice to ground everything; but the +5V does not need to be connected to the phone, only to the Joycon.

                    The point being he can power the Joycon from elsewhere and just use the phone's D+ and D- for the USB communication, and of course share a ground to the phone.
                    Yes... I am doing this in my Truck or will be. Already tested it on the bench and worked fine.
                    Ground and data lines going to computer...
                    Red and ground coming from a modified car charger I hard wired to the USB hub.

                    Rodney

                    Comment


                    • #11
                      Yes, you can power a phone while connected to the Joycon Exd by splitting the USB cable.

                      But the phone will never draw more than 500mA.

                      If you want to run any navigation app that uses GPS and keeps the screen on, this won't be sufficient and the phone will discharge since it will be consuming more than 500mA.

                      The only way to allow a phone to received more than 500mA is to short the data pins at the phone end of the cable - which of course then means it can't connect to the Joycon over USB.

                      The only solution to this would be a viable Bluetooth interface for the Joycon Exd. Which I've yet to find ...

                      Comment


                      • #12
                        OK, I KNOW it can be done, but with a little circuit trickery.

                        What you would need to do is add a small time delay relay circuit to the Joycon, such that when you depress a steering wheel button, and the Joycon detects it, it outputs a signal to switch the relay, which you wire to open the normally closed D+ and D- and hold it open for say 30 seconds to allow the Joycon as being connected.

                        You would need to find out what the shorting resistor value typically used for the D+ and D-, and add that value of resistance into the N.C. circuit, probably 100-1K ohms would work fine. This is just a safety feature to protect the USB controller on your phone.

                        So you press a steering wheel button of choice, the relay opens, a few seconds later your Joycon is detected as connected by your phone, you use the buttons you want, like volume, next track, etc...

                        After the timeout period the relay closes again, and say 100 ohm resistor is effectively shorted across the D+ and D-, and your phone starts charging again.

                        Too much work? Just wire in a data shorting switch somewhere to toggle between Joycon or Phone Charging.

                        Comment

                        Working...
                        X