The SMCA protocol is an NMEA 0183-compatible string used for connecting to helideck monitoring systems and other related systems.
Data:
-
Roll, pitch
-
Heave
-
Surge, sway
Format:
$PSMCA,±xx.xxx,±yy.yyy,±hh.hh,±ss.ss,±ww.ww<CR><LF>
|
SMCA protocol description |
|||||
|---|---|---|---|---|---|
|
FIELD N. |
FIELD |
DESCRIPTION |
UNIT |
TYPE |
NOTE |
|
0 |
$PSMCA |
identifier |
- |
string |
Telegram identifier. |
|
1 |
±xx.xxx |
roll angle |
[deg] |
DBL |
sign: positive (+) is port up, negative (-) is port down. xx.xxx : ‘xx' is the integer part of the roll represented by two digits in range [-99,99], ‘.’ is decimal separator and 'xxx’ is the fractional part of the roll represented by three positive digits in range [0,999]. |
|
2 |
±yy.yyy |
pitch angle |
[deg] |
DBL |
sign: positive (+) is bow down, negative is (-) bow up. yy.yyy: ‘xx' is the integer part of the pitch represented by two digits in range [-99,99], ‘.’ is decimal separator and 'xxx’ is the fractional part of the pitch represented by three positive digits in range [0,999]. |
|
3 |
±hh.hh |
heave |
[m] |
DBL |
sign: positive (+) is upward w.r.t reference plane, negative (-) is downward w.r.t reference plane. hh.hh: ‘hh' is the integer part of the heave represented by two digits in range [-99,99], ‘.’ is decimal separator and 'hh’ is the fractional part of the heave represented by three positive digits in range [0,99]. |
|
4 |
±ss.ss |
surge |
[m] |
DBL |
sign: positive (+) is forward (bow direction), negative (-) is backward (stern direction). ss.ss: ‘ss' is the integer part of the surge represented by two digits in range [-99,99], ‘.’ is decimal separator and 'ss’ is the fractional part of the surge represented by three positive digits in range [0,99]. |
|
5 |
±ww.ww |
sway |
[m] |
DBL |
sign: positive (+) is starboard right, negative (-) is port left. ww.ww: ‘ww' is the integer part of the sway represented by two digits in range [-99,99], ‘.’ is decimal separator and 'ww’ is the fractional part of the sway represented by three positive digits in range [0,99]. |
Example:
SMCA frame with raw example data is listed below.
$PSMCA,+00.060,-02.513,+00.01,+01.86,-00.79<CR><LF>
|
Field 0 |
Field 1 |
Field 2 |
Field 3 |
Field 4 |
Field 5 |
|---|---|---|---|---|---|
|
$PSMCA |
+00.060 |
-02.513 |
+00.01 |
+01.86 |
-00.79 |
Decoded values:
-
Roll
-
Raw value: +00.060, decoded roll angle: 0.06 degrees
-
-
Pitch
-
Raw value: -02.513, decoded pitch angle: -2.513 degrees
-
-
Heave
-
Raw value: +00.01, decoded heave: 0.01 meters
-
-
Surge
-
Raw value: +01.86, decoded surge: 1.86 meters
-
-
Sway
-
Raw value: -00.79, decoded sway: -0.79 meters
-
Note 1
The fields of data (e.g., ‘xx.xxx’) are decimal numbers with leading zeroes where appropriate.
Note 2
The reference frame for data (e.g., roll) is configurable in the SMCA protocol. Also, the data's location (e.g., MRU or MP1) is configurable.