How does odroid xu-4 connect with MX-28R?

[Nicolas]

You probably have troubles around TTL to RS485 conversion. You should have a direction flag added to TTL track to set the RS485 driver on TX or RX mode. Control this flag is an extremely difficult thing with a no real time linux.
You should look at the subject around Hipi board :

Poppy 1.1 : Hipi

Odroid Board used for poppy humanoid (U3) disappearing some month ago, so we switch to a new odroid version (XU4). This board is excessively powerful but there is no sound interfaces and a really dirty integration into the head of poppy humanoid. We choose to switch to RaspberryPi but USB2AX need to be mount out of the head on the usb ports. We started to redesign a new RaspberryPi based on compute module called Raspopyno, but it is relatively expensive and there is only the RaspberryPi 1 versi…