Failed to access to single-bit field about cppreg HOT 4 CLOSED

struct Peripheral {
  struct bxCAN : RegisterPack<0x4000'6400, 1024> {
    // Filter initialization mode
    // When defining the PackedRegister the offset must be in bits! so (0x200)*8 = 4096
    using FINIT =
        Field<PackedRegister<bxCAN, RegBitSize::b32, 4096>, 32, 0, read_write>;
  };
};

struct Peripheral {
  struct bxCAN : RegisterPack<0x4000'6400, 1024> {
    // Filter initialization mode
    using FINIT =
        Field<PackedRegister<bxCAN, RegBitSize::b32, 0x200>, 32, 0, read_write>;
   constexpr static auto active_mode = FINIT::type{0x2A1C0E00};
   constexpr static auto initialization_mode = FINIT::type{0x2A1C0E01};
  };
};

// ...

void can_t::init_filters_() {
  Peripheral::bxCAN::FINIT::write<Peripheral::bxCAN::initialization_mode>();
  
  // ... magic ...

  // Turn all filters initialization -> active
  Peripheral::bxCAN::FINIT::write<Peripheral::bxCAN::active_mode>();
  while (Peripheral::bxCAN::FINIT::read() != Peripheral::bxCAN::active_mode) __nop();
}

// width is 1 bit not 32.
using FINIT =
        Field<PackedRegister<bxCAN, RegBitSize::b32, 4096>, 1, 0, read_write>;