各位大虾：
我用OP3和s7-300作项目，可是用protool编译好的程序怎么也下载不到OP3中，提示如下：
Download version 5.003

2 types of download are possible for this device. Refer to menu item PC Interface...
E4018: Protocol error with MPI connection 0332204DH
Setting up MPI download to OP address 1...
E4018: Protocol error with MPI connection 0332194DH
No connection to the OP!
有那位用过OP3的请指教一下。非常感谢！