SparkFun Forums 

Where electronics enthusiasts find answers.

For the discussion of Arduino related topics.
By MRbling
#199028
Hi,

I'm currently working on a projekt on which an arduino mini is to receive data from an MaxRS485 module.

The data i'm receiving looks like this:

SN=??072? >?>
SN?000?29 ?<>
?N=0?0729?><?
?N=?007?9 >??
SN?000?29?><>?
SN=?007?9 ><?
SN=00?72? ><?
SN?0007?9 >?>
SN?00?729?><>
S?=0?0729?><>?
S?=0?072? ><??

It's supposed to be:

SN=000729 ><>

What is the typical problem when data gets interfered with like this?

The Arduino Mini and the MAXRS485 has different supply voltages. Could this be the issue?


Thanks
By paulvha
#199035
Even though they are different supply voltages, i assume you have connected the GND/0V otherwise you would not get the data. How much different are the supply voltages ? How have you connected ? Are you using softserial and what speed ? what is the test setup ?
By MRbling
#199042
Yes, softserial. 115200 baud when writing commands to the RS485 device and 9600 Printing it in terminal.
I changed from a arduino mini to an UNO and it looks much better but i still get some interferance from somewhere. I have tried all sorts of signal wires but it dont work.
By paulvha
#199049
Your problem is probably the line speed. If you are lucky softserial works well up to ~57K. (nowhere defined, but had tried it on my UNO). Try reduce the Softserial speed to lower speed ( e.g. 9600) and if that works, try higher speeds.
regards
Paul