A info about COM RS485

[paolo.moro]

Hello!

• Does the Serial Port test module support RS485 — half-duplex, differential signal lines?
• How does it handle bus direction control — via RTS signal, via a dedicated pin, or automatically?
• Does it require a physical loopback connector, or does it support a port-to-port test mode (two RS485 ports connected to each other)?

thanks

[David (PassMark)]

I had this RS485 question 23 years ago.

Situation hasn't changed from 20 years ago. Half duplex probably won't work, at least not without some special adapter.

[paolo.moro]

Uao...
It's been a while... I'll try using a null-modem cable for the test. Let's see how it goes.

Thanks

[David (PassMark)]

It is probably possible to make it work, but no one was ever prepared to paid the development costs involved (and RS485 was never very common, even 20 years ago).