Oh, and I saw some additional discussions about the CIS option for the F11. Unless I remember wrong, and understood things wrong, it is not just a simple PROM. It's a coprocessor, which have logic in addition to whatever microcode the coprocessor need. So no way of just duplicating a PROM to get a CIS. Ah ha! Game over then. Pity. Shall have to keep poking about for bits for the 23Plus then :) Thanks! Al.