Reson SeaBat 8101 Operator'S Manual Download

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Interface Specification Document

6.3.8.3

Packet Type 0x18 (8111 only)

struct

RI_THETA_DATA

{

char

synch_header[4];

synch header {0xff, 0xff, 0x00, 0x00

char

packet_type;

// identifier for packet type (0x18)

char

packet_subtype;

// identifier for packet subtype

unsigned short

latency;

// time from ping to output (milliseconds)

DATA_TIME

data_time;

// time of ping for data packet (0 if no UTC input)

unsigned long

ping_number;

// sequential ping number from sonar startup/reset

unsigned

long

sonar_id;

least significant four bytes of Ethernet address

unsigned short

sonar_model;

// coded model number of sonar

unsigned short

frequency;

// sonar frequency in KHz

unsigned short

velocity;

// programmed sound velocity (LSB = 1 m/sec)

unsigned short

sample_rate;

// A/D sample rate (samples per second)

unsigned short

ping_rate;

// ping rate (pings per second * 1000)

unsigned short

range_set;

// range setting for SeaBat (meters )

unsigned short

power;

// power setting for SeaBat

unsigned short

gain;

// gain setting for SeaBat

// bits

0-6 -

gain (1 - 45)

// bit

(0 = fixed, 1 = tvg)

// bit

(0 = manual, 1 = auto)

unsigned short

pulse_width;

// transmit pulse width (microseconds)

unsigned

char

tvg_spread;

spreading coefficient for tvg * 4

// valid values = 0 to 240 (0.0 to 60.0 in 0.25 steps)

unsigned

char

tvg_absorp;

absorption coefficient for tvg

unsigned char

projector_type;

// bits 0-4 = projector type

bit

pitch

steering (1=enabled, 0=disabled)

unsigned char projector_beam_width;

// along track transmit beam width (degrees * 10)

unsigned short

beam_spacing_num;

// receive beam angular spacing numerator

unsigned short

beam_spacing_denom;

// cross track receive beam angular spacing denominator

// beam width degrees = numerator / denominator

short

projector_angle;

projector pitch steering angle (degrees * 100)

unsigned short

min_range;

// sonar filter settings

unsigned

short

max_range;

unsigned

short

min_depth;

unsigned

short

max_depth;

unsigned

char

filters_active;

// range/depth filters active

// bit 0 - range filter (0 = off, 1 = active)

// bit 1 - depth filter (0 = off, 1 = active)

unsigned char

flags;

// bit 0 - Roll stabilization flag. 0 = off, 1 = on.

unsigned

char

spare[2];

spare field for future growth

short

temperature;

// temperature at sonar head (deg C * 10)

short

beam_count;

// number of sets of beam data in packet

unsigned short

range[n];

// range for beam where n = beam Count

// range units = sample cells * 4

unsigned char

quality[cnt];

// packed quality array (two 4 bit values/char)

// cnt = n/2 if beam count even, n/2+1 if odd

// cnt then rounded up to next even number

// e.g. if beam count=101, cnt=52

// unused trailing quality values set to zero

// bit 0 - brightness test (0=failed, 1=passed)

// bit 1 - colinearity test (0=failed, 1=passed)

// bit 2 - amplitude bottom detect used

// bit 3 - phase bottom detect used
// bytes are populated high order nibble first with the
// higher 4 bits for the first sounding and the lower 4 bits
// for the second sounding
// if beam_spacing-num = 180, bytes are populated low
// order nibble first with the lower 4 bits for the first sounding
// and the higher 4 bits for the second sounding

// bottom detect can be amplitude, phase or both

unsigned short

intensity[n];

// intensities at bottom detect * 8

unsigned short

checksum;

// checksum for data packet

};

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SeaBat 8101 Operator's Manual

6-31

(ISD Rev 1.23) Version 3.02