A scanning line drive circuit includes a shift register having stages, hold circuits, and scanning signal output circuits. The hold circuit holds a shift register output in accordance with a sampling signal which is in an active level in one line period in a video signal period. The scanning signal output circuit outputs a scanning signal to be applied to scanning lines based on the shift register output, a hold output, a period specifying signal indicating whether it is in the video signal period or in a vertical flyback period, and timing signals. The scanning signal output circuit outputs a scanning signal for measurement and writing when the hold output is in a selection level in the vertical flyback period. It is possible to select a scanning line corresponding to the pixel circuits in one row and measure currents or voltages in the vertical flyback period, using a simple circuit.