I²C

I²C, short for Inter-Integrated Circuit and also written I2C, is a serial bus for communicating with addressed devices. It uses a data line and a clock line. NXP’s I²C specification

BetterDisplay offers direct I2C communication as a method of reading EDID. It also uses supported display-communication paths for hardware control and EDID writes. A working video image does not prove that the adapter exposes the required communication service.

Keep the operations separate. Reading identification data examines the display's description; sending DDC controls requests an adjustment; rewriting the device's EDID changes stored identification data. Each has different support requirements and consequences.

See Display EDID for the reading and writing interface, including the safeguards for device writes.