The hexadecimal values in the comments at the ends of the following lines (lines 136 and 137 in the current Open8.vhd) do not reflect the declared binary values:
constant ALU_UPP2 : OPCODE_TYPE := "10010"; -- x"11" constant ALU_RFLG : OPCODE_TYPE := "10011"; -- x"12"
The lines should be:
constant ALU_UPP2 : OPCODE_TYPE := "10010"; -- x"12" constant ALU_RFLG : OPCODE_TYPE := "10011"; -- x"13"
This does not result in a bug, as the VHDL uses the binary values.
Fixed.