The subsystem allows the end-user to build an HDMI 2.1 source device, which negotiates with the targeted HDMI sink device for supported features and capabilities. The communication between the source device(s) and the sink device is implemented through the DDC lines, which is an I2C bus included on the HDMI cable.
The following table shows the Data Display Channel interface signals.
| Name | I/O | Width | Description |
|---|---|---|---|
| ddc_scl_i | I | 1 | DDC serial clock in |
| ddc_scl_o | O | 1 | DDC serial clock out |
| ddc_scl_t | O | 1 | DDC serial clock tri-state |
| ddc_sda_i | I | 1 | DDC serial data in |
| ddc_sda_o | O | 1 | DDC serial data out |
| ddc_sda_t | O | 1 | DDC serial data tri-state |