Hardware and software to capture discrete pixel intensity transitions from a small patch of an LCD screen. Transitions are reported as 5V TTL pulses. This device is used to provide ground-truth measurements of frame onset times in visual stimulus presentation (e.g. with PsychToolbox; http://psychtoolbox.org/ ).
The bill of materials and other documentation is available at: https://sites.google.com/site/frame2ttl
Frame2TTL is a product of Sanworks LLC, licensed under GPL v3.0 (see included license) http://sanworks.io