Example pin electronics includes driver circuitry to output a first optical signal to a UUT. The first optical signal is based on a first signal representing first informational content and one or more second signal representing first parametric information. Receiver circuitry receives a second optical signal from the UUT. The second optical signal is related to a third signal representing second informational content and one or more fourth signal representing second parametric information. Comparison circuitry obtains parametric data representing at least one of the first parametric information or the second parametric information, and compares, based on the parametric data, the at least one of the first parametric information or the second parametric information to one or more thresholds. Control circuitry adjusts at least some of the first parametric information prior to output of the first optical signal, and one or more of the thresholds.