大致就是读取1-16个模拟量值，然后整体转换成浮点，标定量程。我能整体读取，但不知怎么转换。
FUNCTION FC38:VOID //读端口AI
//KNOW_HOW_PROTECT
VAR
AI_W, N : INT;
END_VAR
BEGIN
FOR N := 1 TO 16 BY 1 DO
CASE N OF
1 : AI_W := 256;
ELSE:
AI_W := AI_W+2;
END_CASE ;
DB17.AIVALUE[N] := PIW[AI_W];
END_FOR;
END_FUNCTION