DVI (Digital Visual Interface) and HDMI (High-Definition Multimedia Interface) have emerged as the dominant standards for connecting digital display devices like a PC monitor and HDTV. DVI only carries uncompressed video data, whereas HDMI can transfer both uncompressed digital video and multi-channel audio over a single cable. Developed specifically to address the unique requirements of the consumer electronics market, HDMI offers additional enhancements including the support of the YCbCr color space format, and the universal remote control capability through Consumer Electronics Control (CEC) protocol. HDMI-enabled display devices are backward-compatible with DVI-based PCs so users can display the PC contents on their HDTV.
DVI is a video interface standard created by the Digital Display Working Group (DDWG) to replace the legacy analog VGA connector standard. It is designed for carrying uncompressed digital video data to a display. This reference design focuses on DVI-D mode. DVI handles a single-link bandwidth up to 165 MHz and thus supports UXGA and HDTV with resolutions up to 1600 x 1200 at 60 Hz. Higher resolutions can be supported with reduced blanking periods or with a dual-link connection.
HDMI is an industry-supported, all-digital audio/video interface for transmitting both uncompressed digital video and multi-channel audio over a single connector and cable that replaces various cables behind the home entertainment center. HDMI can carry eight channels of 192 kHz, 24-bit uncompressed audio, or any flavor of compressed audio format such as Dolby or DTS. HDMI has the capacity to support existing high-definition video formats such as 720p, 1080i, and 1080p. Because HDMI is electrically compatible with the DVI signal, no signal conversion is required, nor is there a loss of video quality when a DVI-to-HDMI adapter is used.
Reference Designs
Two separate reference designs are implemented for demonstration:
- features the HDMI interface
- features the DVI interface
Both reference designs have been validated using the LatticeECP3 Video Protocol Board and HDMI Mezzanine Card. The reference design consists of the HDMI Transmitter and Receiver cores which are compatible with both HDMI and DVI physical layer protocols. You can use this design to evaluate the SERDES-based HDMI/DVI physical layer solution for your specific application.
HDMI Loopback Demonstration
In the loopback demonstration, the incoming HDMI signal is split into the video and data components and looped back through the output. In addition to this various maipulations are possible on both the data as well as the video.