46 OEM4 Family Installation and Operation User Manual Rev 12Chapter 4 Operation2. Save this with a convenient file name (e.g. C:\GPS\BOOT.TXT) and exit Notepad.3. Ensure that the HyperTerminal settings are correctly set up to agree with the receiver’scommunications protocol. These settings can be saved (e.g. C:\GPS\OEMSETUP.HT) for use infuture sessions. You may wish to use XON / XOFF handshaking to prevent loss of data.4. From the Transfer menu, use the Send text file selection to locate this file to be sent to thereceiver. Once you double-click on the file or select Open, HyperTerminal will send the file to thereceiver.4.3 Transmitting and Receiving CorrectionsCorrections are transmitted from a base station to a rover station to reduce or eliminate errorsintroduced by system biases, as described in Section 6.1.1, GPS System Errors on Page 67. In mostcases you will need to provide a data link between the base station and rover station (two NovAtelreceivers) in order to receive corrections. Exceptions are the SBAS and OmniSTAR L-band capablereceivers. However, if you wish to use other types of corrections for these receivers, a data link mustbe provided. Generally a link capable of data throughput at a rate of 2400 bits per second or higher issufficient for the examples shown below.Next you need to pre-configure the base and rover site receivers before the units are used in yourapplication.At the base station, enter the following commands:interfacemode port rx_type tx_typefix position latitude longitude heightlog port message [trigger [period]]For example:RTCA interfacemode com2 none rtcafix position 51.11358042 -114.04358013 1059.4105log com2 rtcaobs ontime 2log com2 rtcaref ontime 10log com2 rtca1 ontime 10 3log com2 rtcaephem ontime 10 7RTCM interfacemode com2 none rtcmfix position 51.11358042 -114.04358013 1059.4105log com2 rtcm3 ontime 10log com2 rtcm22 ontime 10log com2 rtcm1819 ontime 2log com2 rtcm1 ontime 10 5CMR interfacemode com2 none cmrfix position 51.11358042 -114.04358013 1059.4105log com2 cmrobs ontime 2log com2 cmrref ontime 10log com2 cmrdesc ontime 10 5At the rover station, enter:interfacemode port rx_type tx_type
