不知道怎么回事m20.0的值上来就是1，所以加了一个ld sm0.1 复位m20.0
Network 1
LD SM0.0
R Q0.2, 3

Network 2
LD SM0.1
R M20.0, 1
Network 3 // 网络标题
LDN M20.0
END
Network 4
LDB= 0, VB399
JMP 0

Network 5
LDB= 1, VB399
JMP 1

Network 6
LDB= 2, VB399
JMP 2
Network 7
LBL 0
Network 8
LD SM0.0
S Q0.2, 1
END
Network 9
LBL 1

Network 10
LD SM0.0
S Q0.3, 1
END
Network 11
LBL 2
Network 12
LD SM0.0
S Q0.4, 1