M4-CYGMINI-TSR-M-ENG_Iss 1
Cygnus MINI ROV Operation Manual
Page 53 of 66
15.
Serial Data Format
The CygLink program and TSR are provided to automatically
decode the measurement data sent from the Gauge, and to
provide a calibrated display of the results. For users who want to
display and log the data using their own software such as
StarFix
®
, this section describes the arrangement of the data sent
from the Gauge.
Note the Cygnus MINI ROV Gauge has a fixed Velocity of Sound
value of 6400 m/s, you must re-scale the received thickness value
for the velocity of sound required.
For example when measuring carbon steel with a velocity of 5920
m/s you will need to apply the following conversion factor:
True Thickness = Received Thickness * 5920/6400
Protocol
1.
Unidirectional - Gauge transmits only
2.
Eight Data bits, 1 Start bit, 1 Stop bit, No Parity; 2400
baud
3.
Four packets per second
4.
Valid-Reading
packet-length : 7 bytes
5.
No-Reading
packet-length
: 3 bytes
Valid Thickness Measurement Packet Arrangement
Byte
1
2
3
4
5
6
7
Name SOH
Status
Data1 Data2 Data3 Data4
ETB
Type
1h
ASCII ASCII ASCII ASCII
17h
No Thickness Measurement Packet Arrangement
Byte
1
2
3
Name SOH
Status
ETB
Type
1h
17h