RS485 Serial communication not working.

I am refering to this example.

I have two industruino devices connected as per shown in above link the sender code is working fine. But at the reciever device no result.

At reciver end  lcd.print(Serial.available()) = 0 and = -1;

Sunil Mali
Sunil Mali
| 4 1 1
Asked on 3/4/20, 8:40 AM

Hi, are you using the exact code as in the link example? It does not print the Serial.available() and it only does when Serial.available() > 0

Make sure your wires are correct A to A, B to B and both INDIOs have to be powered with external 12/24V


| 1 1 3
Answered on 3/4/20, 9:50 AM

In the example code I have just added print lines for available and read in loop. and connection is also A to A, B to B. As for power is concern I have used USB cable.

Sunil Mali
on 3/4/20, 12:06 PM

USB cable only powers up the topboard, not the base, so RS485 will not work with USB power only

on 3/4/20, 12:13 PM

Is power voltage 12/24V is mandatory?

Sunil Mali
on 3/4/20, 12:14 PM

Hi Tom, is RS485 will work with 5v supply? I trying with 5V and 2Am adapter the base LEDs are lights up but not able to get result.

Sunil Mali
on 3/5/20, 12:31 PM

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Asked: 3/4/20, 8:40 AM
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Last updated: 3/4/20, 9:50 AM