[WetCoast]

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Did I download the wrong software?
Do I need to download some other software that would include that library?
Do I need to include some other libraries that come with Arduino 1.8.8?

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Hi Gord,

I think you did everything the right way!
I checked the Pro2 Compact software package and found that I forgot to include the libraries required to compile the TX software.
I already have updated the software package with the missing libraries. Please download it again.
Sorry for this mistake, and thank you for having reported it.

Regards

Thanks.
It's getting better, or at least different.
Now I get the following error message.
I can find the DHTxx directory and the DHTxx.cpp file but I don't see a sub directory off DHTxx (or anywhere) named util.
I can find atomic.h in libraries/RadioHead_TeensyVersion/RHutil

Code:

Arduino: 1.8.8 (Linux), Board: "LOLIN(WEMOS) D1 R2 & mini, 80 MHz, Flash, Enabled, 4M (no SPIFFS), v2 Lower Memory, Disabled, None, Only Sketch, 921600"

/home/gord/Arduino/libraries/DHTxx/DHTxx.cpp:6:25: fatal error: util/atomic.h: No such file or directory
#include <util/atomic.h>
                        ^
compilation terminated.
exit status 1
Error compiling for board LOLIN(WEMOS) D1 R2 & mini.

This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.