Garmin GI 275 Installation Manual page 260

Mfr Model
Garmin SL30
190-02246-14
Rev. 11
Data Format Interfacing Equipment Configuration Information
With no external CDI connected to SL30, set INDICATOR HEAD TYPE:
SERIAL.
With external "standard CDI" connected to SL30, set INDICATOR HEAD
RS-232
TYPE: RESOLVER.
With external "composite CDI" connected to SL30, set INDICATOR HEAD
TYPE: SERIAL.
Notes
Can be NAV 1, NAV 2, or both.
Software v1.3 or later required.
GI 275 STC EIS & MFD Installation Manual
Page C-6