loading
I1.2I0.2I0.1Q0.0I1.1Q0.1( )I1.2I0.4I1.2I0.5I1.2I0.6I1.2I1.0I0.2I1.2I1.0I0.4I1.2I1.0I0.5I1.2I1.0I0.6Q0.1I0.1I1.2T37INTON50PT100msI1.2I0.3I0.4I0.2Q0.2I1.1Q0.3( )I1.2I1.0I0.3I0.4Q0.3图3-2 程序梯形图 3.4 指令表 指令编程是另一种PLC编程方法，指令表也可以很容易从梯形图得到，本设计具体指令表如下。
Network 1 LD I1.1 O M0.3 AN I1.0 = M0.3 Network 2 LD I1.3 O I1.4 O M0.1 = M0.1 Network 3 LD I1.3 O M0.0 AN I1.4 = M0.0 Network 4 LD M0.1 A I1.0 O M0.2 AN Q0.0
AN I0.0 AN I0.1 AN I0.2 AN I0.3 AN I0.4 AN I0.5 AN I0.6 = M0.2 Network 5 LD M0.0 A I0.2 LD I1.0 CTU C48, 1 Network 6 LDN I1.2 A M0.2 O Q0.0 LDN I1.2 A T37 AN C48
OLD LD I1.2 A I1.0 A M0.2 OLD LDN C48 A I1.0 A I1.2 OLD
AN M0.3 AN I0.4 AN I0.2 AN I0.0 AN Q0.2 AN I0.5 AN I0.6 AN Q0.1 AN I0.3 AN I1.1 = Q0.0
Network 7 LDN I1.2 A I0.0 O Q0.2 LD I1.2 A I1.0 A I0.0 OLD AN I0.4 AN I0.5 AN I0.6 AN I0.3 AN Q0.3 AN I1.1 = Q0.2 Network 8 LDN I1.2 A I0.2 LDN I1.2 A I0.4
OLD LDN I1.2 A I0.5 OLD LDN I1.2 A I0.6 OLD LD I1.2 A I1.0 A I0.2 OLD LD I1.2 A I1.0 A I0.4 OLD LD I1.2 A I1.0 A I0.5 OLD LD I1.2
A I1.0 A I0.6 OLD O Q0.1 AN I0.1 AN Q0.0 AN I1.1 = Q0.1 Network 9 LD I0.1 AN I1.2 TON T37, 50 Network 10 LDN I1.2 A I0.3 AN I0.4 LD I1.2 A I1.0 A I0.3 AN I0.4
OLD O Q0.3 AN I0.2
AN Q0.2 AN I1.1 = Q0.3
3.5 小结
本章主要介绍了系统的软件设计，在了解了PLC软件编程的基本知识和方法步骤后，本设计采取了先采用梯形图编程后，再写出软件指令的基本思路，完成系统的软件设计。
在软件设计中，采用了先简易、后复杂的思路。在编写过程中先完成连续工作和单周期工作方式的软件编写，然后在这两种工作方式的基础上结合步进工作方式的具体特点，编写出步进工作方式的程序，然后对照程序梯形图写出程序指令表，从而完成整个系统的软件编写工作。