Touch frame setup

Measurement

1. Measure viewable glass width × height in millimetres.
2. Order a frame rated for that active area — not the plastic TV bezel.

Physical install

1. Clean glass aggressively — oils break IR beams.
2. Mount frame per vendor clips — keep parallel edges; twist causes false touches.
3. Route USB cable down the same chase as Pi HDMI so it does not dangle in front of sensors.

Linux / Chromium

1. Plug USB — lsusb should list a HID multitouch device.
2. If axes inverted, swap X/Y or rotation in Settings → Input → Touch (build-dependent) or udev rules.

Troubleshooting

Ghost touches
Direct sunlight hitting sensors — add brow; recalibrate via vendor utility if provided.

Dead band at edges
Oversized frame — remeasure active area.