Techniques for variable forward error correction

A system includes an encoding circuit, a line quality monitor circuit, and a controller circuit. The encoding circuit generates a first data signal indicating encoded data using a first forward error correction code. The line quality monitor circuit generates an indication of a line quality of a second data signal using an eye monitor circuit that monitors the second data signal. The controller circuit causes the encoding circuit to generate encoded data in the first data signal using a second forward error correction code in response to a change in the indication of the line quality of the second data signal.