HDMI ARC (Audio Return Channel, HDMI 1.4) and eARC (Enhanced ARC, HDMI 2.1) allow audio to flow back from TV to soundbar over the same HDMI cable, eliminating separate optical or RCA audio cables.
| Pin | Name | Function | Type |
|---|---|---|---|
| 1-12 | TMDS Data/Clock | Standard HDMI video and audio | BUS |
| 13 | CEC / ARC | Consumer Electronics Control and ARC data | BUS |
| 14 | eARC- / Reserved | Enhanced ARC negative or reserved (HDMI 2.1) | BUS |
| 15 | SCL | DDC I2C clock | BUS |
| 16 | SDA | DDC I2C data for EDID | BUS |
| 17 | DDC/CEC GND | Ground | GND |
| 18 | +5V | 5V DDC power | PWR |
| 19 | Hot Plug Detect | Hot plug and eARC detect | I/O |