hb4.tdf

DEMO2 数码管扫描显示电路/DEMO4 计数时钟 DEMO5 键盘扫描设计/DEMO6 波形发生器/DEMO7 用DAC实现电压信号检测/DEMO8 ADC电压测量/DEMO9 液晶驱动电路设计

SUBDESIGN hb4
(
   clk,d[7..0]			:INPUT;
   q[3..0],sel      	:OUTPUT;
)

VARIABLE
   count:	DFF;
BEGIN
   count.clk=clk;
   sel=!count.q;
   
   IF(count.q==VCC) THEN
      count.d=GND;
   ELSE
      count.d=VCC;
   END IF;
   
   CASE count.q IS
      WHEN VCC =>
                q[]=d[7..4];
      WHEN GND =>
                q[]=d[3..0];
   END CASE;  
END;