Eduard Lebedyuk · Jan 9, 2019

Work with devices connected via RS422/RS485

I connected from InterSystems Cache to devices connected via RS232 (commonly known as COM-port).

Can the same be done with devices connected via RS422/RS485 interfaces?

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Yes, this makes no difference at software level and should work exactly the same with RS422/485 as with RS232.

The difference is that with RS232 the hardware cable uses single-ended signals, with RS422/485 the cable uses differential signals. In addition, RS485 can transport signals over much longer cables and can talk to multiple devices connected to the same cable, in that case a protocol with device uid's is needed.

So Caché can talk in an identical way to a RS485 device, but the (software) protocol will probably be different.

You'll need also a hardware device (converter/bus driver) to convert the RS232 signals from your pc/server to RS485 differential signals.