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I have the FT232RLMG device and a device that uses the RS-485 connection standard. I would like to know if I can connect the TX and RX pins of the FT232RLMG to the device that uses RS-485 directly or do I need some more components?

I have looked for information in the datasheet and found that it specifies in the section typical applications:

  • USB to RS232 / RS422 / RS485 Converters

In the and in technical characteristics says:

  • Data transfer rates from 300 baud to 3 Mbaud (RS422, RS485, RS232) at TTL levels.

Link to datasheet: FT232R

Thank you very much.

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  • \$\begingroup\$ No, you cannot connect it directly to either RS-232 or RS-485. In either case an appropriate inverting level shifter and possibly differential converter is required to go from the IC's logic level to the interface signalling standards. \$\endgroup\$ – Chris Stratton Dec 30 '16 at 16:07
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RS-485 uses differential signaling

RS-232 uses single ended signaling

They are not directly hardware compatible.

There are many off the shelf hardware devices that convert from RS-232 to RS-485. I believe single IC components exist as well although the ones I've worked with are RS-232 at 5V and 3.3V logic levels (UART) not full RS-232 voltage levels.

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    \$\begingroup\$ This mostly misses the point - the FT232 ICs support neither RS-232 nor RS-485, a product based on one which supports those must include a line driver and receiver from the USB IC's logic level to the interface standard level and polarity. \$\endgroup\$ – Chris Stratton Dec 30 '16 at 16:06

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