USB to TTL serial cable with RS485

Hello all,

Does anyone know if it’s possible to use a USB to TTL serial cable for RS485 protocol?

The cable in question:

I would like to use above mentioned cable with Infinity integration on Bryant furnace without buying USB to RS485 serial converter.

Reading through, Rpi requires USB to RS485 serial converter.
I only require RX/TX pins TTL does support up to 3.3V, while RS485 recognize any differential voltage >200mV with a voltage range of -7V to +12V.

I guess I am answering my own question if anything over 3.3V will damage.

This is my go to cable for flashing sonoffs and don’t want to destroy it.

Thank you all,

It’s been awhile, and not for Home Assistant, but from some work I was doing programming PLC’s bit I use a USB to RS-232 converter and then this device:

HXSP-485B RS-232 To RS-485 Converter
https://www.hexin-technology.com/RS-232_To_RS-485_Converter-Product-257.html
looks like USD 18 on ebay today, don’t remember what I paid
so that price plus a ‘regular’ USB to RS-232 cable

Thanks, If this cannot be done, most likely will get USB to RS485 converter. Indeed they are cheap these days.

Good hunting…the key question I ask myself before I plug in any ‘Serial’ device be it TTL, RS-232, RS-485, RS-#$%$##$# is what are the voltages? This message comes from my drawer of ‘fried’ devices :wink:

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how can I use a sensor connected to this convertor.