modify examples to avoid corrupting fixed message about tinylora

[brentru]

There are many ways to deal with this. We could have sendData make a local copy of the message, but that is a potential waste of up to 252 bytes.

Thank you for reminding me about this, I remember we spoke about this issue a few weeks back.

I opened a new branch for this issue (https://github.com/adafruit/TinyLoRa/tree/fix-encrypt) which copies over the packet to in lora.sendData(data) to a new character array which is fed as an argument to the Encrypt_Payload function and doesn't modify the original Data value sent through sendData().

Tested on my Feather 32u4 and TTN and received the same payload back every frame, instead of garbled like before.

[jerryneedell]

In the "fix-encrypt" branch the tmpData can only handle a fixed size 10 byte message. This needs to handle any message length up to the maximum of 252 byte (I think).
I'm still not convinced that sendData needs to be changed to make a copy- I think it better to have the user take responsibility for creating a fresh packet for every transmission. I don't think this is a real burden since most uses would likely involve changing data from sensors and would be different for every packet anyway.

[brentru]

A patch for this issue has been merged into master. Closing...