本人采用PROFIBUS－DP通讯协议控制变频器，当SUB-D连上通讯板时，系统提示故障，英文说明如下：
Data transmission problem of the CP5613/CP5614 !
-> Cause:
a) short circuit on the bus line
b) problems with the bus terminator
c) defect station
d) wrong bus parameters (double station address, TTR is too low, wrong baudrate, ..)
e) other disruptions.
请求解答，千万火急！！