Prolog basics

The Prolog is a module that can be added to Nortek instruments in replacement of the standard recorder. It is installed in the location as the static recorder. The pure recorder variant uses an industrial grade SD card with 4 GB of memory. The industrial grade SD card is sealed and watertight, which is in line with the Nortek philosophy that the data should still be available even in the event of damage to the instrument that leads to a leakage.

The Prolog can have added wave processing functionality when used with an AWAC. Data may then be streamed over the serial line of the AWAC in either binary format or as NMEA ASCII strings. When wave processing is enabled the processed data – as well as raw data - is stored on the SD card. Below is a detailed description of both the binary data formats and the NMEA data strings that the user would need to either convert or parse.

Note that the AWAC software includes the conversion of the processed binary data file (*.WPB) found on the SD card. This is found under the ASCII data conversion tool.

More information about the use and description of the data products is found in instrument deployment software (e.g., AWAC AST software).

The serial output may be either binary or ASCII, but not both. The current profile and sensor data is always streamed out amongst the data structures when serial output is activated. The user can select the different processed data types output when wave processing is enabled; wave parameters are always output.

When the current profile is to be followed by a wave measurement, the profile data is output together with the processed wave data. Otherwise the current profile is output at the end of the average interval.

It is possible to use the Prolog in an emulation mode where a raw AWAC data file (*.WPR) is re-processed. This can be done either using the configuration in the WPR-file on the SD card or using the configuration set with the AWAC software. These two emulations of wave processing and data streaming is started with the commands EWFF (Emulate Wave File configuration) and EWSS (Emulate Wave Software Setup), respectively. When either of these commands are sent to the AWAC (in a terminal emulator program, such as the AWAC’s), the ProLog will open the first WPR-file it finds. If serial output is enabled there will be a 10 second delay before the processing is started to allow connection to another serial port. Data are, as during regular measurements, always output to file and also output on the serial port according to the configuration (NMEA, binary, SeaState online format). If the SeaState online format is used the station configuration is output before the wave processing starts.

ASCII serial data is output according to NMEA standard. The format does not follow the NMEA standard strictly (no limits on length), but uses this standard as the basis for comma separated data.

The specific formats are found in the system integrator manual available at http://www.nortek-as.com/en/support/application-development