Hi Peter,
since this CPU is managing MMI (Men-Machine-Interface) in 6 languages (switchable), so I need an external Eprom (I'm using 27c4000, which is becoming a little small and so I will have to upgrade to 27c8000...).
Is there any other alternative on CPU's?
Increasing the clock as Erik proposes is not an alternative due to the rest of the timings on the bus (memory / peripherals).
Regards,
Gerardo