Is there a more detailed code example on cross-chain

`https://github.com/bttcprotocol/bttc-doc/blob/master/docs/tron-bttc.md#deposit`
There are a lot of nouns here. I don't know how to get the contract corresponding to this method, and whether there is a shortcut link to help me find it faster.

eg: 
- `ERC20Predicate` 
- `rootTokenABI`, `rootTokenAddress`
- `rootChainManagerABI`, `rootChainManagerAddress`

and more nouns