clk clk rst rst extrst_low extrst_low state_qout[2:0] state_qout[2:0] serial_port serial_port go go done done d[7:0] d[7:0] ser_cycle_go ser_cycle_go ser_cycle_done ser_cycle_done serclk serclk ser_q ser_q counter[11:0] counter[11:0]