(for desktop computers and displays) and "embedded profile" (for the internal display of a laptop computer). Under the external profile, data was transmitted using three differential data pairs and one differential clock pair using the TMDS encoding scheme. The external profile is considered an extension of HDMI and is backwards-compatible with HDMI Rev. 1.2 displays; however, UDI does not carry audio information as it is targeted towards high-resolution computer monitors instead. As HDMI is itself an extension of DVI with HDCP, UDI external profile is compatible with these standards as well. The embedded profile was slightly different, using either one or three differential pairs, each of which carried both data and clock information. The embedded profile uses an ANSI 8b/10b encoding scheme instead. UDI provided higher bandwidth than its predecessors (up to 16 Gbit/s in its first version, compared to 4.95 Gbit/s for HDMI 1.0) and incorporated a form of digital rights management known as HDCP. Connector The external and embedded connector implementations were electrically compatible and physically similar, each with a single row of contacts, but they had different form factors and contact counts. The "embedded" implementation was only specified for the display panel interface and had a single row of 26 contacts, while the "external" implementation had a single row of 22 contacts inside a metal shield with a physically keyed rectangular cross-section, resembling the USB Type A connectors. The contacts were spaced on a pitch of (external) and (embedded). Three of the contacts were reserved for future upgrade possibilities. Transmit and receive plugs and receptacles were different physically, similar to peripheral cables with USB-A and USB-B on each end, requiring the UDI cable to be plugged in one way only. Bidirectional communication worked at a much lower data rate than that available for the single direction video datastream. Notes References External links Digital display connectors High-definition television