在硬件里查看cpu属性时，默认的cyclic interrupt只有OB35可以设置， 怎样设置才能修改其他OB的呢？ 下面是我新建了一个OB30，但在download to plc时提示出错 S7tgtopx.exe: =========== 05/14/2004 12:11:38 下午===================== S7tgtopx.exe: Download (33:53772): (D20C) OB cannot be copied as the associated priority class does not exist. S7tgtopx.exe: Download (294:23): Unable to copy the block test\SIMATIC 300(1)\CPU 314\S7 Program(1)\Blocks\OB30. Do you want to continue the copy procedure? -- Help on Message 33:53772 Description of Error: Message from the module. To Correct or Avoid Error: Note the restrictions of the module being used. Check which organization blocks are permitted on the module or are currently active.