When connecting a touchscreen to the Onefinity controller there are a few key items to make it work correctly:
Step 1: POWER: Every screen must be connected to external (wall) power to operate correctly. Skipping this step is the most common mistake users make. On the 7 and 8" screens, the 12v wall power adapter must be connected to the 12v in (red arrow) port. On the 10", there is no 12v power input, instead, a USB C port labeled with a lightning bolt is used (red arrow). This cable must be plugged into the supplied 5 volt, 3 amp USB wall power brick to wall power. Without using external power, the screen will flicker during use.
Some sized screens have a circular port labeled ‘HP’ that can be confused as the 12v power in port. The ‘HP’ port is for headphones. DO NOT plug in the 12v power adapter into this port. Doing so will damage the screen. It is also important to have the controller and screen power plugged into one circuit, and the router and vac on a completely different circuit as the controller and screen. DO NOT plug them all in together into one power strip!
Step 2: TOUCH: For the screen to get its ‘touch’ ability, the USB C cable plugs into the USB C port on the side of
the 7,8, and 10" screens (the usb c port not labeled with the lightning bolt in the case of the 10" screen) (red
arrow) and the other end must be connected to any one of the 4 usb ports on the back of the Onefinity controller. This connection enables the ‘touch’ ability.
Step 3: VIDEO SIGNAL: Finally, the HDMI cord provides the video signal. One end will go to the touch screen port labeled HDMI (Green arrow) and the other into the HDMI port in the back of the Onefinity controller. It is important that the screen is powered on via the screens own power button 5-10 seconds before turning on the Onefinity controller. The controller ‘learns’ what screen resolution to output to from the screen but to do so the screen must be on before the controller.
Screen Aspect Ratio/Resolution/touch calibration
To get the right video size/calibration, ALWAYS turn the screen on BEFORE turning on the controller. The controller reads the screen (if it’s on) to know what size it should adjust to before displaying video. If the screen is turned on after the controller, you may have black bars on top and bottom of the screen and the ‘touch’ input will be off by a few mms.
EMI, Flickering, Black or Blank screen:
If you have verified you have the cables connected correctly and the screen is blinking on and off during a cut, you may be experiencing EMI. Ensure you have the controller and screen on one outlet, and the vacuum and spindle/router on a separate circuit/outlet. If that does not correct the issue, consider placing ferrite cores on each cable that connects to the screen: https://amzn.to/2XDpH0O
What is emi? Electromagnetic interference - Wikipedia
Symptoms of not connecting correctly, touch doesn’t work and screen flickers black.
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