ELSIF #A=2 AND #B=#C THEN
        CASE #D OF
            11..19:
                #H:= 'In->Pause:Button';
                #F := -1;
               #G:= 6;
                #D := 10;
            21..29:
               #H:= 'OUT->Pause:Button';
                #F := -1;
               #G:= 6;
                #D :=  20;
            101..109:
                #H:= 'In->Pause:Button';
                #F := -1;
               #G:= 6;
                #D :=  100;
                
        END_CASE;
    END_IF;

這段程序什么意思？特別是  In->Pause:Button  這是什么啊，新手不明白

'OUT->Pause:Button'   用引號了。說明是字符串。