Operation Chapter 4OEM4 Family Installation and Operation User Manual Rev 12 47For example:RTCA interfacemode com2 rtca noneRTCM interfacemode com2 rtcm noneCMR interfacemode com2 cmr noneFor compatibility with other GPS receivers, and to minimize message size, it is recommended thatyou use the standard form of RTCA, RTCM or CMR corrections as shown in the examples above.This requires using the INTERFACEMODE command, refer to Volume 2 of this manual, to dedicateone direction of a serial port to only that message type. Once the INTERFACEMODE command isused to change the mode from the default, NOVATEL, you can no longer use NovAtel formatmessages.If you wish to mix NovAtel format messages and RTCA, RTCM or CMR messages on the same port,you can leave the INTERFACEMODE set to NOVATEL and log out variants of the standardmessages with a NovAtel header. ASCII or binary variants can be requested by simply appending an"A" or "B" to the standard message name. For example on the base station:interfacemode com2 novatel novatelfix position 51.11358042 -114.04358013 1059.4105log com2 rtcm1b ontime 2At the rover station you can leave the INTERFACEMODE default settings (interfacemode com2novatel novatel). The rover receiver will recognize the default and use the corrections it receives witha NovAtel header.The PSRDIFFSOURCE and RTKSOURCE commands set the station ID values which identify thebase stations from which to accept psuedorange or RTK corrections respectively. They are usefulcommands when the rover station is receiving corrections from multiple base stations. With thePSRDIFFSOURCE command, all types may revert to SBAS if enabled using the SBASCONTROLcommand. Refer to Volume 2 of this manual for more details on these commands. See Section6.2,Satellite-Based Augmentation System (SBAS) on Page 68 for more information on SBAS.At the base station it is also possible to log out the contents of the standard corrections in a form that iseasier to read or process. These larger variants have the correction fields broken out into standardtypes within the log, rather than compressed into bit fields. This can be useful if you wish to modifythe format of the corrections for a non-standard application, or if you wish to look at the correctionsfor system debugging purposes. These variants have "DATA" as part of their names (e.g.RTCADATA1, RTCMDATA1, CMRDATAOBS, and more). Refer to Volume 2 of this manual fordetails.Chapter 5, Message Formats on Page 54 describes the various message formats in more detail.
