HDMI Madhav Achar, Patrick D’Agostino, and Arthur Rajala EECS 373 March 2014 University of Michigan 1

Purpose Protected data transmission Real world embedded systems Future coursework:

What is HDMI? ●High Definition Multimedia Interface ○ Audio/video transmission Video uncompressed Audio compressed or uncompressed ●By 2013, over 3 billion HDMI devices sold ○ Surpassed DVI in 2008 [1] ●Possible alternative for 373 projects ○ No HDMI port on Smartfusion boards ○ Raspberry Pi, Arduino TRE, BeagleBoard 3

Technical Specifications HDMI 1.0 [2] December 9, GB/s, 3.95GB/s without overhead <= 60Hz 8 audio channels 192 kHz audio sampling frequency Supports HDCP Same video format as DVI HDMI 2.0 [3] September 4, GB/s, 14.4 GB/s without overhead <= 60Hz ● 32 audio channels ● 1536 kHz audio sampling frequency ● Supports HDCP ● Backwards compatible connector 4

High-bandwidth Digital Content Protection (HDCP) 1.Authentication of receiver a. Shared secret session key b. Authenticate any downstream receivers c. Recheck every 128 video frames [4] 2.Encryption of data stream a. Pixels XOR-ed with a changing 24 bit number 3.Key revocation a. Checks for compromised device 5

Pin Connections Pins 1-9:3 TMDS Channels Pins 10-12:TMDS Clock Pin 13:CEC Pin 14:ARC/HEC (1.4) Pin 15-16:DDC Pin 17:Data shield Pin 18:Power supply (+5V) Pin 19:Hot plug detect 6

Display Data Channel (DDC) HDCP authentication Automatic Device Configuration o Video/audio format on receivers o Precise latency data to keep synchronization Unidirectional I2C bus o 100 kbit/s minimum 7

Transition Minimized Differential Signaling (TMDS) ●Interleaves video, audio, auxiliary data 3 transmission periods o Video data o Data island o Control 8b/10b encoding using bitflipping, XOR/XNOR Audio clock recovery 8

Consumer Electronics Control (CEC) Controls up to 15 connected devices ○ Used for One Touch Play, System Standby, Menu control, etc ●One-wire bidirectional bus based on AV.link [5] ○ Open collector ○ Value determined by low period 9

CEC Example 10

Example Project Using HDMI 11

What are the alternatives? VGADVIHDMI DisplayPort Pros No strict resolution limit 2048 x 1536 standard cable limitation Same format as HDMI 1080p Video and audio 2160p (2.0), 1080p (1.0) 30 fps 2160p Audio and video ● 60 fps Cons Only Video Analog signal interference Only video Fees Ports only appear on computers 12

Cables and Cost Cost to the manufacturer o Large manufacturers: $10,000 per year Additional $0.15 per device Reduced to $0.05 if HDMI logo used Reduced to $0.04 if HDCP implemented o Small volume manufacturers: smaller yearly fee, pay more per device Types of Cables o Standard (Type I) cables tested to 75MHz, or up to 2.25 Gb/s (720p/1080i) o High Speed (Type II) cables tested to 340MHz, or 10.2 Gb/s (2560x1600) 13

Conclusion Powerful interface for multimedia content o Audio, video, device control o High bandwidth o Automatic configuration o Data protection Popular, standard in embedded systems o Need separate board for 373 o Used for other EECS courses 14

Sources 1."HDMI Specification Marks 10-Year Milestone as De-Facto Standard for HD Connectivity". HDMI Licensing, LLC Retrieved "HDMI Specification Marks 10-Year Milestone as De-Facto Standard for HD Connectivity" HDMI Specification Version 1.3a, Supplement 1: Consumer Electronics Control (CEC)HDMI Specification Version 1.3a, Supplement 1: Consumer Electronics Control (CEC) D0802DFEF646E602/HDCP%20on%20HDMI%20Specification%20Rev2_2_Final1.pdfhttp:// D0802DFEF646E602/HDCP%20on%20HDMI%20Specification%20Rev2_2_Final1.pdf content/uploads/2013/09/HDMI-logo_black-1600px_610x130.pnghttp://web.archive.org/web/ / content/uploads/2013/09/HDMI-logo_black-1600px_610x130.png 11. %20Audio%20Transport%20over%20HDMI%20-%20AES% pdfhttp:// %20Audio%20Transport%20over%20HDMI%20-%20AES% pdf