User Manual

element14 is a trademark of Premier Farnell plc 68

6.10.2 HDMI Framer

The

TDA19988

is a High-Definition Multimedia Interface (HDMI) 1.4a transmitter. It is

backward compatible with DVI 1.0 and can be connected to any DVI 1.0 or HDMI sink.

The HDCP mode is not used in the design. The non-HDCP version of the device is used

in the element14 BeagleBone Black design.

This device provides additional embedded features like CEC (Consumer Electronic

Control). CEC is a single bidirectional bus that transmits CEC over the home appliance

network connected through this bus. This eliminates the need of any additional device to

handle this feature. While this feature is supported in this device, as of this point, the SW

to support this feature has not been implemented and is not a feature that is considered

critical. It can be switched to very low power Standby or Sleep modes to save power

when HDMI is not used.

TDA19988

embeds I

C-bus master interface for DDC-bus

communication to read EDID. This device can be controlled or configured via I

C-bus

interface.

6.10.3 HDMI Video Processor Interface

The

Figure 44

shows the connections between the processor and the HDMI framer

device. There are 16 bits of display data, 5-6-5 that is used to drive the framer. The

reason for 16 bits is that allows for compatibility with display and LCD capes already

available on the original BeagleBone. The unused bits on the

TDA19988

are tied low. In

addition to the data signals are the VSYNC, HSYNC, DE, and PCLK signals that round out

the video interface from the processor.