How do the tries work that are used in the mmo object format's symbol tables?

I try to understand, how the mmo object file format works, which is used for Don Knuth's educational MMIX architecture开发者_如何学Go. I have not bought MMIXware, so I have to guess most of the details from the literate source files of the assembler and simulator.

The object format uses a special ternary search trie for storing the symbol table. At a look at the code, I don't quite understand how it works. Can somebody please explain me some details? Especially about how the tree is serialized.

I don't think I can do much better than the explanation found here.