Thank you. The fact that TrueRNG v3 can be read as a serial device helped a lot. I have written an article about how to use a TrueRNG with the GCP at this link:
https://gacimartin.com/2017/12/10/creating-an-gcp-egg-node-with-a-raspberry-pi-and-a-truerng-hardware-random-number-generator/
Thanks for your quick and deep support.