Our communications scripts expect a telebit 2500 or 3000 modem.
Our Refteks acquire 32 bit data, have 3 channels running at 50 sps continuously. This configuration is necessary for our data download algorithm to work (though other sample rates could be accomodated with a change of parameters). Our algorithm to calculate what disk sector at which to start the file transfer requires that the data be continuously acquired, and only include one stream.
We added extra memory to our Refteks to handle the fact that Refteks stop acquiring data if their memory fills up while a file is being transferred. Memory is written out to disk prior to a file transfer, so we put in the extra memory, and for long downloads, when memory would fill up, we download multiple smaller files which are concatenated together to make the final file. Our algorithm expects 2.5MB of memory.
Although not required, we have found it convenient to have a fairly large disk on our Refteks so that we can have some time to determine whether we want to download data before it gets overwritten. Our disks are 228MB which hold a bit over 4 days worth of data (at 32-bit, 3 channels, 50 sps).
Our field engineer has put into each Reftek a relay which allows us to center the mass remotely with a command over the phone line. This is another convenience issue.
Refmenu - ASCII menu driven Reftek administration script - We use this Mlink script to manage the Refteks. When we are installing a new station or there are problems that we need to diagnose, we use this to access the Reftek and send it various commands. Also, this program can be put in terminal mode after connecting with a Reftek to access the modem at the Reftek. We have all modems in front of the Refteks set up to allow remote access of modem settings.
Mlink call script for refteks-
We have an Mlink script which is used by the
SPYDER®
system to
download data from reftek dataloggers based on a SPYDER® request file.
The SPYDER® system automatically receives
e-mail notification of events from our automatic real-time seismic
processing system,
SUNWORM and generates requests for data from stations
based on magnitude/distance criteria. These requests are then processed
automatically, in near-real-time.
Refgetdata - This script can be run as an "at" job, and downloads data from Refteks based on requests it finds for data in an ASCII file. This file can contain multiple requests for data, for multiple stations. We use this script for smaller events and teleseisms which didn't trigger our SPYDER® system (and so for which we have no near-real-time need of the data).
Refrestart - This script is used to reset the reftek to start writing at the beginning of its disk. It can be convenient to run this as an "at" job after the download script has run.
Diskcalc - The program to calculate the disk sector at which to start data download (and used by refgetdata) is a 'C' program that could be modified to handle different data sizes, sample rates and number of channels.