Network Data Server Access

version

int version = 0xb;

revision

int revision = 4;

status channels 3

0000 for OK or an error code in the same format.
The rest of the fields are in ASCII, separated by the new line character. Integers are decimal. String could be up to 255 characters in length.

int num_channels;

for (int i = 0; i < num_channels; i++) {
  char channel_name[];
  int sampling_rate;
  int data_type; // 1-short; 2-int; 3-long; 4-float; 5-double; 6-complex float
  int tp_num;  // Test point number, zero is sent for the DAQ configured channels.
  int channel_group_num; // Almost disused; 1000 -- DMT channel, 1001 - obsolete
  char unit[];
  float gain;
  float slope;
  float offset;
}

header (length,
             seconds,
             gps,
             seq_num)

long length;  // 16 + following data block's length
long seconds; // time series data length for what is following next in the data block
long gps; // GPS time of the first sample in the following data block
long gps_nanoseconds; // GPS time nanosecond fraction of the first sample in the following data block
long seq_num; // Sequencial number of this block; Starts with zero.

data_block

time series data grouped by channel (not by time) at the sampling rate requested in 'start net-writer' command. If requesetd two channels then in this data blocks server sends data for the first channel and then data for the second channel.

signal_conv

float signal_slope;
float signal_offset;
int data_valid; // Data Valid code for the following data

reconfig_block

header(seconds = -1) followed by reconfiguration data in the following format:
signal_conv_t[n], where n = (header length - 16)/16;
Reconfiguration blocks can be inserted in the data stream of blocks at any point and there is normally one reconfiguration block in the beginning of data transmission, in front of the very first data blocks.

gps

Get current GPS time

header(length = 16), ie. no data just header with current GPS time

start net-writer {
"H2:LSC-CARM_CTRL" 128
"H2:LSC-MICH_CTRL" 128
"H2:LSC-PRC_CTRL" 128
"H2:LSC-DARM_CTRL" 128
 "H2:LSC-LA_NPTRX" 128
}

Request full resolution online data on the same socket. All channels are wanted at 128 Hz sampling rate. Data is averaged and decimated by the server. Data is not filtered. Requesting data at lower sampling rate is only usefull for display purposes.

header
reconfig_block
data_block[N]

start trend net-writer  775155636 600 { "H2:SUS-SM1_SUSPIT_INMON.min" "H2:SUS-SM1_SUSPIT_INMON.max" "H2:SUS-SM1_SUSPIT_INMON.mean"
}

Request 600 seconds of second trend data.

header
reconfig_block
data_block[N]

start trend 60 net-writer "7001" 775669072 86400 { "H2:IOO-PZT1_PIT_OFFSET.min" "H2:IOO-PZT1_PIT_OFFSET.max" "H2:IOO-PZT1_PIT_OFFSET.mean"
}

Get minute trend data and route to  TCP port 7001 on requestor's host. Time period of data requested is 775669072 upto 775669072 + 86400 (ie. 86400 is the time series data length in seconds). Channel names wanted are specified in double quotes in curly braces.

header
reconfig_block
data_block[N]