Arduino Pro Mini and NPK Sensor

Using Arduino Project Guidance
1

Hi everyone. Thank you for the replies for the past few forums. I really appreciate what you are all doing here.

I have a question regarding these components: A 3.3V Pro Mini, an NPK sensor, and an SX1276 module transmitter. The NPK sensor is connected via an RS485 to TTL module, such as the one shown below. The operating voltage of the RS485 to TTL module is 5V.

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Here comes the question. I want to plug the TTL module's pins - DI, DE, RE, and RO - to the 3.3V Pro Mini. I am concerned though with the logic levels coming from the module to the Pro Mini.

Is this viable? What should I do if the approach is not viable?

Thanks everyone.

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Always use level shifter between 5 volt and 3.3 volt logic. A 3.3 volt output can be connected to a 5 volt logic device, but not the opposite.
For specific advice, read and use this link: How to get the best out of this forum - Using Arduino / IDE 1.x - Arduino Forum

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Not a good choice for a 3.3V Pro Mini.

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there are TTL to RS485 breakout module which work at 3.3V available on ebay in UK
I have used such modules on an ESP32 which uses 3.3V logic without problems

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