The TL485 is an RS485 adaptor designed specifically for the CC18/16’s communication (programming) port. This port is not RS232, but CMOS/TTL levels. The TL485 converts it to 2-wire (half duplex) RS485. A special feature of the TL485 is that it provides automatic switching between transmit and received modes, by sensing when the CC16 starts transmitting. With this you can have up to 32 separate devices exchanging ModBus data at 9600BPS.
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