Variable HashTypeConst

 0b0000000 0
   ───┬─── │
      │    ▼
      │   type - use the default vm version
      │
      ▼
data* - use a particular vm version

Implementation of blockchain.mol https://github.com/nervosnetwork/ckb/blob/5a7efe7a0b720de79ff3761dc6e8424b8d5b22ea/util/types/schemas/blockchain.mol