REF: BBONEBLK_SRM
BeagleBone Black System
Reference Manual
Rev A5.2
Page 65 of 108
6.9.4
HDMI Control Processor Interface
In order to use the TDA19988, the processor needs to setup the device. This is done via
the I2C interface between the processor and the TDA19988. There are two signals on the
TDA19988 that could be used to set the address of the TDA19988. In this design they are
both tied low. The I2C interface supports both 400kHz and 100KhZ operation.
Table 9
shows the I2C address.
Table 9.
TDA19988 I2C Address
6.9.5
Interrupt Signal
There is a HDMI_INT signal that connects from the TDA19988 to the processor. This
signal can be used to alert the processor in a state change on the HDMI interface.
6.9.6
Audio Interface
There is an I2S audio interface between the processor and the
TDA19988
. Stereo audio
can be transported over the HDMI interface to an audio equipped display. In order to
create the required clock frequencies, and external 24.576MHz oscillator,
Y4
, is used.
From this clock, the processor generates the required clock frequencies for the
TDA19988.
There are three signals used to pass data from the processor to the
TDA19988
. SCLK is
the serial clock. SPI1_CS0 is the data pin to the
TDA19888
. SPI1_D0 is the word sync
pin. These signals are configured as I2S interfaces.
