Technical reference

Integrated standby flight display (M4f)

docs/ISFD.md

Zibo's ISFD from the 737-800's PANEL_3D (LU_ISFD, group STANDBY Horizon, 34 datarefs; panel rectangle from the UVs of b738_cockpit.obj line 31881) with Zibo's bitmaps. Instrument lu737-isfd, dark unless L:LU737_ISFD_PWR = 1 (electrics). Expected look docs/isfd_cruise.png.

  • Systems module standby/ (build 20), from zibomod CMD_standby_alt_* and Systems: BARO knob (0.01 inHg, or 1 hPa = 0.0295 inHg in HP, 0 … 40 inHg, not in STD), HP / IN, STD, APP (off → ILS → B/CRS → off: horizontal and vertical deviation scales), brightness + / − (0.05 steps, 0.8 at the flight start), standby altitude 145366.45 × (1 − (p / baro)^0.190284) on MSFS's static pressure, followed at 2 /s within −5000 … 47000 ft as zibomod. Published L:LU737_ISFD_* and the button states L:LU737_KNOBS_STANDBY_ALT_*.
  • Display sources: ISFD_SOURCES in avionics/src/du/NdSources.ts; attitude / IAS / heading / deviations from MSFS, IRS flags, init time (electrics). Oracle xphost/test/sci/isfd_trace.json → avionics/test/data/isfd_oracle.json.
  • Renderer: the ISFD's IAS and altitude readouts are X-Plane rolling digits (gen_rolling), now drawn by PanelView (odometer columns on the 14-cell strip under the -3 mask).
  • Not rewritten: baro sync with the captain / FO and the RMI variant (Zibo EFB options, off), GLS / FAC deviations (FMS).