The custom function would be nice :-) As commented in another thread before:
The AP_SPD_Cmd for the Rotate MD88, depends on 3 custom Xrefs. The standard Xref: (sim/cockpit/autopilot/airspeed) is for some reason actually holding the display value for the AP_VS_Cmd when the AP IAS pitch mode is selected - showing the current knots- or mach value. This IAS function is similar to the levelchange (where speed is controlled by pitch).
The 3 parameters for AP_SPD_Cmd are:
XRef -- Value -- Simvim Parametername
'Rotate/md80/autopilot/spd_is_mach' -- 0,1 -- AP_IAS_Mach_On
'Rotate/md80/autopilot/at_target_mach' -- 0.5-1? -- AP_SPD_Mach?? (new parameter suggestion - if necessary)
'Rotate/md80/autopilot/at_target_speed' -- 100-500? -- AP_SPD_Kts
The output to show depends on the spd_is_mach value: When this xref is 1 the display must show the mach value, else the Kts value. I've looked at the Conditions function - but it doesn't seem to allow every simvim-parameters as input condition parameters. Are this kind of logic allowed in simvim? The above intermediate values does not necessarily have to be public disposed if you have another solution for this implemented.