Trying to communicate s7 200 smart plc with GS HMI of Mitsubishi

Hi All

          I am trying to communicate s7 200 smart plc with GS HMI of Mitsubishi make. We have short connected the RDA and SDA pin of the HMI and connected to RS485A pin to the plc , short connected RDB and SDB pin of the HMI and connected to RS458B of the PLC and pin number 1 of the PLC and pin number 5 of the HMI to ground. We have selected the corresponding driver in the hmi and made correct settings of the communication. We are unable to establish the communication, Kindly suggest any solution.

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Split from S7-200 smart commuication with non siemens HMI.