16bit 计数器

<p><span style=";font-size:17px;font-family:黑体;color:rgb(35,31,32)">&nbsp;</span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">一般用计数器和停电保持用状态的分配，可通过系统参数配置进行变更设定。 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">对于 </span><span style=";font-size:13px;font-family:Arial;color:rgb(35,31,32)">16bit </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">计数器，其有效设定值为</span><span style=";font-size:13px;font-family:Arial;color:rgb(35,31,32)"> K1 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">～ </span><span style=";font-size:13px;font-family:Arial;color:rgb(35,31,32)">K32,767 (10 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">进制常数）；设定值</span><span style=";font-size:13px;font-family:Arial;color:rgb(35,31,32)"> K0 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">和 </span><span style=";font-size:13px;font-family:Arial;color:rgb(35,31,32)">K1 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">具有相同效果，即在 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">第一次计数开始时输出触点就动作。如下例： </span><span style=";font-size:13px;font-family:Arial;color:rgb(0,0,0)">X6 </span><span style=";font-size:13px;font-family:Arial;color:rgb(0,0,0)">X5 </span><span style=";font-size:13px;font-family:Arial;color:rgb(0,0,0)">1 </span><span style=";font-size:13px;font-family:Arial;color:rgb(0,0,0)">2 </span><span style=";font-size:13px;font-family:Arial;color:rgb(0,0,0)">3 </span><span style=";font-size:13px;font-family:Arial;color:rgb(0,0,0)">4 </span><span style=";font-size:13px;font-family:Arial;color:rgb(0,0,0)">5 </span><span style=";font-size:13px;font-family:Arial;color:rgb(0,0,0)">6 </span><span style=";font-size:13px;font-family:Arial;color:rgb(0,0,0)">7 </span><span style=";font-size:13px;font-family:Arial;color:rgb(0,0,0)">8 </span><span style=";font-size:13px;font-family:Arial;color:rgb(0,0,0)">9 </span><span style=";font-size:13px;font-family:Arial;color:rgb(0,0,0)">C10 </span><span style=";font-size:13px;font-family:Arial;color:rgb(0,0,0)">Y1 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">计数输入 </span><span style=";font-size:13px;font-family:Arial;color:rgb(35,31,32)">X5 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">每驱动 </span><span style=";font-size:13px;font-family:Arial;color:rgb(35,31,32)">C10 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">线圈一次，计数器的当前值就增加，在执行第 </span><span style=";font-size:13px;font-family:Arial;color:rgb(35,31,32)">9 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">次的线圈指令时，输出触点动作。 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">以后即使计数输入 </span><span style=";font-size:13px;font-family:Arial;color:rgb(35,31,32)">X5 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">再动作，计数器的当前值不变。如果复位输入 </span><span style=";font-size:13px;font-family:Arial;color:rgb(35,31,32)">X6 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">为 </span><span style=";font-size:13px;font-family:Arial;color:rgb(35,31,32)">ON</span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">，则执行 </span><span style=";font-size:13px;font-family:Arial;color:rgb(35,31,32)">RST </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">指令，计数器 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">的当前值清为 </span><span style=";font-size:13px;font-family:Arial;color:rgb(35,31,32)">0</span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">，输出触点复位。 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">计数器的设定值，除用上述常数 </span><span style=";font-size:13px;font-family:Arial;color:rgb(35,31,32)">K </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">设定外，还可由数据寄存器编号指定。如上例中，指定 </span><span style=";font-size:13px;font-family:Arial;color:rgb(35,31,32)">D20</span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">，如果 </span><span style=";font-size:13px;font-family:Arial;color:rgb(35,31,32)">D20 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">的内容为 </span><span style=";font-size:13px;font-family:Arial;color:rgb(35,31,32)">9</span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">，则与设定 </span><span style=";font-size:13px;font-family:Arial;color:rgb(35,31,32)">K9 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">是一样的。 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">在以 </span><span style=";font-size:13px;font-family:Arial;color:rgb(35,31,32)">MOV </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">等指令将设定值以上的数据写入当前值寄存器时，则在下次输入时，输出线圈接通，当前值寄存 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">器变为设定值。 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">对于一般用计数器，如果切断可编程控制器的电源，则计数器的计数值被清除，而停电保持用的计数器则可 </span><span style=";font-size:13px;font-family:宋体;color:rgb(35,31,32)">存储停电前 的计数值，因此计数器可接着上一次数值累计计数。</span></p>