ADIRU.
In addition to questions raised and answers given.
The lowest speed value on the speed scale = 60 knots.
CAS set itself on 0 and invalid (NCD) if CAS < 30 Knots (SPD FLAG).
MACH will be 0 and invalid (NCD) if M < .1 = (MACH FLAG).
ADIRU 3 data (normally ISIS) can be used by LH or RH PFD by means of rotary switch.