
error: Cannot read the value of o.back because it is an output with type inv &uint<8>
    ┌─ ports.py:26
    │
 26 │ s.o.back.assert_eq("0")
    │ ^^^^^^^^^^^^^^^^^^^^^^^ Cannot read from o.back

  Help: The field has type inv &uint<8>
  Help: Since this is an output, only signals with non-inv type can be read

