Welcome to the forum.
It is because the link is made before discourse moved to a new platform, over a year ago. I could probably renew the link, but info is outdated.
Mma is not used anymore.
Use bno085 or cmps 14
Today go the teensy way.
Kaupoi can be used together with a teensy panda board
Search for the word panda with the magnifying glass at top right.
One is this Aio 5.6 - #4 by m_elias