Xbee 232 485 communication

Other & Legacy Products
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I’m trying to improve my understanding of how these things work so would appreciate it if anyone can help me.

I have managed to get communication going back and forth using XBees and 232 Explorer shields and am now looking at 485.

I went with a 232 shield for the XBee as it obviously does more than just connect the right pins to the D-Sub (I did try that first) but I don’t really know what.

Now I’m looking at 485 comms I’m having trouble finding a current 485 shield, especially one that isn’t very expensive.

Then I found this thread

https://forums.parallax.com/discussion/160057/passing-rs485-bus-data-between-two-xbee

Few years old but the last comment discusses a way that you can do 485 comms without a 485 chip which, I guess is what I’m also using on the Explorer board (but a 232 one obviously).

Does this mean there is a way for me to send and receive 232 from an XBee without a conversion chip / board? And the same for 485?

Has anyone on here done these things?

Thanks

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The XBee products are 3V CMOS level devices. If your Processor or device is also a 3V CMOS level device, then you can connect the XBee directly to it without the use of a level shiftier.

RS485 does require a chip as you are using one of the radios line as a TX Enable. Also the radio does not offer true RS485 as that is either 4 wires (two for Tx and two for Rx) or 2 wire (Differential Tx Rx lines).

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Thanks mvut again for your help

I see, so I suspect I the reason my 232 comms didn’t work is that the device I’m connecting to is 5V (I think), does that sound right?

And using a 485 chip would allow me to use the 2 available pins on the XBee and the chip would do the necessary conversions?

So is what the person said on that thread not possible then?

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Yes that does. You must use a level shifter between the two devices for it to work.

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No, using an RS485 chip will not give you more lines. You have the same Tx Rx lines for RS232. You actually reduce it by 1 line as you need to use a TX Enable pin where by on RS232 you do not.