User manual SIMRAD EM REV M

[. . . ] Instruction manual EM Series Multibeam echo sounders Datagram formats Kongsberg EM Series Multibeam echo sounder EM datagram formats 850-160692/M January 2010 Document history Document number: 850-160692 Changes: A new output datagram, Network Attitude Velocity datagram 110, is added. The 3 D velocity input is used for Doppler compensation in FM mode. The range corrections applied is documented in the Raw range and angle 78 datagram. Installation, Runtime and status datagrams are updated with extra information. [. . . ] is also explained in the "External sensors" chapter in the SIS Reference Manual. 2. 7. 1 KSSIS 80 Datagram Sound velocity and temperature sent over LAN (UDP) to SIS HWS Table 21 KSSIS 80 input datagram Data Description Start identifier = $ Talker identifier Sentence formatter Datagram ID Sound speed (m/s) Temperature (Celsius) End if sentence delimiter = CRLF End if sentence delimiter = CRLF Format Always 24h Always KS Always SIS, Always 80, x. x, x. x Always 0Dh 0Ah Always 0Dh 0Ah Valid Range -- -- -- -- 1400. 0 ­ 1. 700 -- -- -- Note -- -- -- -- -- -- -- -- 850-160692/M 39 Kongsberg EM Series 3 OUTPUT DATAGRAMS Topics · · · · · · · Introduction on page 40 Multibeam data on page 43 External sensors on page 64 Sound speed on page 75 Multibeam parameters on page 78 PU information and status on page 97 SIS generated output on page 105 3. 1 Introduction Output datagrams are usually logged to disk on the EM Series Operator Station. The output datagrams may also be exported to user provided programs on the Operator Station or on an external Ethernet network using UDP protocol (remote logging). An NMEA DPT depth datagram may be exported on a serial line. The output datagrams are mostly in binary format using signed or unsigned integer numbers with lengths of 1, 2 or 4 bytes. With a PC based operator station little endian is normally used, while big endian is used on Unix work stations. The same byte order as used on the operator station is used for the output datagrams. Note Please be aware that the use of big endian is not maintained on the newer sounders (EM 3002, EM 710, EM 302 and EM 122), since the operator station is PC based running Windows or Linux. Note We recommend that software written to decode EM Series data includes a check for the byte ordering with a provision for byte swapping. Suitable data fields to check on are the length field at the start of the datagram, the EM Series model number field and possibly the date and time fields. The basic output datagram structure established with the EM 100 echo sounder is retained. · All datagrams (except the NMEA DPT datagram) start with STX, datagram type and time tag, and end with ETX and checksum (sum of bytes between STX and ETX). In addition the total length of the datagram (not including the length field) will precede the STX byte, given as a four byte binary number. 40 850-160692/M Output datagrams · The length field is only included when logging to tape and/or disk, but not for datagrams logged to a remote location. The length can then be derived from the network software. Systems logging data remotely should add this length at the start of each datagram. This length is required if the data are to be used with Kongsberg Maritime post-processing systems. · The time stamp resolution is 1 millisecond and includes the century. The date is given as 10000*year(4 digits) + 100*month + day, for example 19950226 for February 26, 1995. All date fields in the output datagrams use this format. A time is usually given (in milliseconds) from midnight. · The datagrams identify the multibeam echo sounder model and its serial number. The system model number is 120 for the EM 120, 300 for the EM 300, etc. For the EM 3000D (the dual head system) the model number was originally given as 3002 and the serial number is that of Sonar Head number 1. However in the depth datagram model numbers 3003-3008 are now used to also identify the actual transmit and sampling frequencies of the two heads. If only one head is activate on the EM 3000D, it is coded as a single head system. [. . . ] The EM model number and checksum are required. 2 May not be implemented for all sounders. 3 The sensor input status is coded in accordance with that given in the PU Setup datagram, but indicates which sensor datagram types are actually being received on the respective ports. 4 0 or a negative number indicates that the quality of the data received is not acceptable, positive OK. [. . . ]