A power system includes a power semiconductor devices; a control circuit outputting first firing signals each being for a corresponding power semiconductor device, and outputting first activation response signals each being associated with a corresponding power semiconductor device. A first interface circuit cooperates with the control circuit to input a first serial signal and output the first firing signals, and to input the first activation response signals and output a second serial signal. A second interface circuit cooperates with a controller to input the second serial signal, to output to the controller second activation response signals corresponding to the first activation response signals, to input from the controller second firing signals corresponding to the first firing signals, and to output the first serial signal. The controller controls the power semiconductor devices with the second firing signals, and monitors the power semiconductor devices with the second activation response signals.