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RS-232C |  |
RS-422 |  The wiring in the terminal resistance must be 330 Ω. To improve the stability of communication, devices should connect through SG, using STP cables. Shielded cables must be earthed. |
RS-485 |  The wiring in the terminal resistance must be 120 Ω. When using RS-485, connect SDA and SDB, but disconnect RDA and RDB. To improve the stability of communication, devices should connect through SG, using STP cables. Shielded cables must be earthed. |