看到这样一个程序FB201
L 4
NEXT: T #temp0

L #temp0
L 1
-I
SLD 3
LAR1


O DIX [AR1,P#4.0]
O
A DIX [AR1,P#0.0]
AN DIX [AR1,P#4.0]
= DIX [AR1,P#8.0]
A DIX [AR1,P#4.0]
A DIX [AR1,P#0.0]
R DIX [AR1,P#0.0]

O DIX [AR1,P#4.1]
O
A DIX [AR1,P#0.1]
AN DIX [AR1,P#4.1]
= DIX [AR1,P#8.1]
A DIX [AR1,P#4.1]
A DIX [AR1,P#0.1]
R DIX [AR1,P#0.1]

O DIX [AR1,P#4.2]
O
A DIX [AR1,P#0.2]
AN DIX [AR1,P#4.2]
= DIX [AR1,P#8.2]
A DIX [AR1,P#4.2]
A DIX [AR1,P#0.2]
R DIX [AR1,P#0.2]

O DIX [AR1,P#4.3]
O
A DIX [AR1,P#0.3]
AN DIX [AR1,P#4.3]
= DIX [AR1,P#8.3]
A DIX [AR1,P#4.3]
A DIX [AR1,P#0.3]
R DIX [AR1,P#0.3]

O DIX [AR1,P#4.4]
O
A DIX [AR1,P#0.4]
AN DIX [AR1,P#4.4]
= DIX [AR1,P#8.4]
A DIX [AR1,P#4.4]
A DIX [AR1,P#0.4]
R DIX [AR1,P#0.4]

O DIX [AR1,P#4.5]
O
A DIX [AR1,P#0.5]
AN DIX [AR1,P#4.5]
= DIX [AR1,P#8.5]
A DIX [AR1,P#4.5]
A DIX [AR1,P#0.5]
R DIX [AR1,P#0.5]

O DIX [AR1,P#4.6]
O
A DIX [AR1,P#0.6]
AN DIX [AR1,P#4.6]
= DIX [AR1,P#8.6]
A DIX [AR1,P#4.6]
A DIX [AR1,P#0.6]
R DIX [AR1,P#0.6]

O DIX [AR1,P#4.7]
O
A DIX [AR1,P#0.7]
AN DIX [AR1,P#4.7]
= DIX [AR1,P#8.7]
A DIX [AR1,P#4.7]
A DIX [AR1,P#0.7]
R DIX [AR1,P#0.7]

L #temp0
LOOP NEXT

FB201的输入管脚是DI模块强制DI0X_M_0至DI3X_M_7和一个DINT型的DIM输出管脚是DI0X_0至DI3X_7
外面有个FC41里面调用FB201，每次调用的时候就在DIM处根据模块输入DI1,DI2.......
哪位大侠帮我看看，解释解释这段程序啊