Mind you: the corruption only occurred during pinging my modem…
Here is the configuration of the 171.
I think the reason is that you use a different Baudrate (9600). I use 115200. With the low Baudrate the answers of the RN171 to the commands and the data that come from the Network are mixed.Try with 115200. My driver should automatically set the Baudrate of the Cerbuino and the RN171 (don’t care the exceptions that come the first time a new Baudrate is set)
Edit: when I try with 9600 sometimes an expected line is missing
Unfortunately the same corrupted data. It looks indeed two serial streams are interfering.
Perhaps 2 thread are interfering in the internal processor of the 171…
1: the command interpreter
2: the output of the pinging proces
Who knows? >:)
Besides the baudrate an interfering factor is the time in which the answer to the ping comes back. In normal operation the device is either in command mode or in data mode, so this issue should not play a role.
Anyhow, an explainable phenomenon, no reason to throw the RN171’s away.
I think that for this issue the case (the ping issue) is closed, I can live with this anomaly.
So now I can continue with the actual question behind the ping isue 
️. After joining the network; what is the best way to detect whether the modem and my ftp-server are ( still) on line?
Perhaps start a new thread on ftp transfer?