Touchscreen or HDMI output

  • Hello,

    RASPAD3 indeed a great product that boost the portability of Pi4. I've been using Pi4 in RASPAD3 for daily driver, and it works great for teaching since i started to receive from KS campaign (~ 1yr ago). My current situation is:

    - to get the touchscreen works (when using RASPAD screen only), I will lose the ability to project raspad screen to secondary display

    - to make HDMI outlet works, i must sacrifice the touchscreen (even no HDMI cable to external display plugged in)

    As i used this mainly for classroom teaching, I weigh on external HDMI to work. Twisting the cable is onlything i can do now to make the RASPAD screen projected to external display.

    Any suggestion is welcomed to make RASPAD function like usual.

    Thanks in advance

  • The touch screen will only work when no external screen is connected that is by design of the raspad team and can only be changed by modifing the mainboard of the raspad, and the team sadly have not been very open with exactly what would need to be changed and for this to work even if they do it would require very fine smb soldering of components to the mainboard and this is not something that can be done by the average end user.

  • Correct it is by design. The problem: the touch screen does work even without external display. 

    To make the touch screen work, i used to twist the hdmi 0 cable when Pi is running till I see the touch works. When the touch screen works, tue other problem comes: i cannot use the external hdmi

    To make the external HDMI work, i twist hdmi 1 cable, restarts several times till projection to external display works. In that case, when i unplugged external hdmi, the touchscreen does not work.

    i am wondering if this is caused by faulty hdmi cables? Or the daughter board?

  • @Andi Dinata yep sounds like a faulty cables hopefully the support team can sort you out with replacements when they see your message :)

  • @Andi Dinata

    First, please check whether the internal usb cable connection is stable.
    Because the touch function will become weird after the external screen is connected, the touch function is directly turned off when the external screen is connected. If the internal hdmi cable is not connected, the raspad3 motherboard will detect that there is an external device, and the touch will also not work.

  • @RasPad Support the USB cable function normally. I think the short hdmi cable (HDMI1) is faulty. I attach 2 pictures below:

    Short HDMI cable is not functional

  • @Andi Dinata 

    When the Raspberry Pi touch is connected to two screens, the touch area will expand to two areas, which will be very strange to use, so after we set the external screen, turn off the touch. It is recommended that you use a mouse and keyboard when connecting to an external screen.
    If you really want to use touch, you need to do software and hardware modifications. Software may be fine. Hardware-wise, you may need to solder jumpers/cut the wiring on the board/solder extra resistors, etc. Since you are using the earliest version of RasPad3, we have not found the hardware test of this version. If you want to change it, you can take a picture of the motherboard and send it to us, and we will help you to see how to modify it.


    In addition, our technician do not quite understand the meaning of your two pictures. Could you express it clearly?

  • @RasPad Support he shows in first iage that with only short hdmi connected the second display does not work.

    second picture using long hdmi  instead the second screen works, so as he says looks like the shorter HDMI cable is faulty.

Please login to reply this topic!