beaglebone-black - Flipbook - Page 60
BeagleBone Black
6.6.1 Supported Resolutions
The maximum resolution supported by the BeagleBone Black is 1280x1024 @ 60Hz. Table 9 below shows the
supported resolutions. Not all resolutions may work on all monitors, but these have been tested and shown to
work on at least one monitor. EDID is supported on the BeagleBone Black. Based on the EDID reading from
the connected monitor, the highest compatible resolution is selected.
Table 6.6: HDMI Supported Monitor Resolutions
RESOLUTION
800 x 600 @60Hz
800 x 600 @56Hz
640 x 480 @75Hz
640 x 480 @60Hz
720 x 400 @70Hz
1280 x 1024 @75Hz
1024 x 768 @75Hz
1024 x 768 @70Hz
1024 x 768 @60Hz
800 x 600 @75Hz
800 x 600 @72Hz
720 x 480 @60Hz
1280 x 720 @60Hz
1920 x 1080 @24Hz
AUDIO
YES
YES
YES
YES
NOTE: The updated software image used on the Rev A5B and later boards added support for 1920x1080@24HZ.
Audio is limited to CEA supported resolutions. LCD panels only activate the audio in CEA modes. This is a
function of the speci昀椀cation and is not something that can be 昀椀xed on the board via a hardware change or a
software change.
6.6.2 HDMI Framer
The TDA19988 is a High-De昀椀nition 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 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~2~C-bus master interface for DDC-bus communication to read EDID. This device can be
controlled or con昀椀gured via I~2~C-bus interface.
6.6.3 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.
6.6. HDMI Interface
55
