GS_GSR_GCR_UserManual_V21.doc / 18.09.2009
GeoSIG Ltd.
GSR / GCR / AS User Manual
Page 13
Table 2. Possible baud rates with serial data stream
Communication speed
1200 Baud
2400 Baud
4800 Baud
9600 Baud
1920
0 Bau
d
3840
0 Bau
d
1152
00 Baud
POM, 3 channels
100
SPS
X
X
200
SPS
X
250
SPS
X
SOM, 3 channels
100
SPS
X X X X
200
SPS
X
X
X
250
SPS
X
X
4.4.1.2. Packet Oriented Mode (POM)
Set-up:
•
Connect the cable from the PC to the RS-232 connector on the Instrument.
•
Log in to the Instrument.
•
Please refer to the GeoDAS manual for further steps.
Starting the serial data mode:
After logging out of the Instrument, it starts automatically the serial data mode after 2 seconds.
Stopping the serial data mode:
After logging in to the Instrument, the serial data mode automatically stops and remains off for the time
being logged in.
Data format:
Standard GSBU protocol is used.
The Instrument can be directly connected to GeoDAS or SEISLOG in the “Packet” mode, which
increases the performance regarding event memory, event detection and online (GeoDAS, SEISLOG)
and offline (SEISAN) analysis enormously.
If SEISLOG is used please go through the SEISLOG manual to look up the settings required for the
Instrument.
5. Functional Description
This section discusses some of the technical details of how the Instrument works. Input signal filtering
and digitising, triggering, time accounting, data storage and event logging are among the function
described.
5.1. Signal Conditioning
Electrical signals from seismic sensors connected to the Instrument are range-adjusted in preparation
for conversion to digital form and are filtered to prevent aliasing effects. The signals are next sampled
and digitised, and then digitally filtered under software control to further reduce noise. Then these data
are used for triggering and recording.
The Instrument accepts signals from sensors within the sensor voltage output ranges as follows:
•
GCR 12 / 16 recorders:
2.5V ± 2.5 VDC
