79REFERENCESetup Menu:InterfaceThe ‘GARMIN’ optionallows the GPS 12 MAPto exchange data with aPC or another GPS 12MAP. Use this settingwith the optional PCSoftware Kit.Over 100 different da-tums are provided to al-low the GPS 12 MAP tocorrespond to variouspaper charts/maps. UseWGS 84 unless yourchart specifies otherwise.To change the position format and/or mapdatum:1. Highlight the ëPosition Formatí or ëMap Datumí fieldand press ENTER.2. Select the desired setting (using the rocker keypad)and press ENTER.Interface SettingsFormat lets you control the input/outputformat used when connecting your GPS 12MAP to external NMEA devices, a DGPSbeacon receiver, a personal computer, etc.Five format settings are available:• GARMIN — the proprietary format usedto exchange waypoint, route, track logdata with a PC or with another GPS 12MAP.• NMEA — supports the input/output ofstandard NMEA 0183 version 2.0 data.• None — provides no interfacingcapabilities.• RTCM/NMEA — allows Differential GPS(DGPS) input using a standard RTCMformat and also provides NMEA 0183version 2.0 output.• RTCM Text — allows DGPS input usinga standard RTCM format, without anyoutput capabilities.• Text Out— allows DGPS output using astandard RTCM format, without anyinput capabilities.