ATLAS North America Proprietary
Sea Scan ARC Scout MKII Operations Manual
1 of 1
Page: 44
Issue: 1.2.4
SCTM2-OPS
Operations Manual
This section provides a description of the Sonar Data Stream and how it should be used. You may find
looking at the C/C++ header file more informative. Please refer to the SDS.H file in the Software
Development Kit (SDK) for more information. If you would like more information, need help with some of
the concepts of the Sonar Data Stream or would like to propose an addition or modification please refer to
the Contact and Support information at the end of this document.
7.1.1
Variable Types
All of the data contained in the sonar data stream is stored as "Little Endian" byte order. The variable sizes
that are used in the SDS.H
header file
as well as in the following section(s) are listed below.
Type
Size in Bytes
Signed/Unsigned
BYTE
1
unsigned
WORD
2
unsigned
DWORD
4
unsigned
int
4
signed
short int
2
signed
float
4
NA
double
8
NA
7.1.2
General Packet Structure
Each Sonar Data Stream packet contains a header and a optional data payload. The packet header is 16
bytes in size and is formatted like this:
Element
Variable Type
Description
dwSize
DWORD
The size of the entire data packet, not
including this header.
dwTimeStamp
DWORD
The number of milliseconds since the
system started.
dwTag
DWORD
This describes the contents of the data
packet and how the header will be used.
byMisc[3]
BYTE
Used for miscellaneous storage.
byChecksum
BYTE
This is a simple 8 bit checksum
calculated by adding all of the bytes in
the packet header (for a total of 15
bytes) into an 8 bit number. This
checksum excludes the byChecksum
variable (the last byte).