Young Ultrasonic Anemometer Voltage and Serial Output Model 85000 - Manual (Page 6)

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85000-90
5.3.2 ASCII
ASCII output provides continuous wind measurement data in text
format. Between each measurement cycle, the sensor goes into a
low power mode. There are a number of parameters related to the
ASCII serial output format which may be altered. Please note that
the default values are recommended for most applications.
Careful analysis of the sensor's application should be done prior to
making changes due to the interaction of parameters such as OUT-
PUT DELAY and SAMPLE COUNT. See section 6.0.
ASCII output appears either in POLAR or CARTESIAN (UV) format.
With POLAR format, the wind speed threshold and wind speed units
are selected. With CARTESIAN format, the threshold is ignored and
wind speed units are always meters per second (m/s).
ASCII POLAR FORMAT
a www.w ddd ss*cc
where
a = Sensor address
www.w = Wind speed (selected units)
ddd = Wind direction (degrees)
ss = Status code
* = Asterisk (ASCII 42)
cc = Checksum
= Carriage return (ASCII 13)
ASCII CARTESIAN (UV) FORMAT
a uu.uu vv.vv ss*cc
where
a = Sensor address
±uu.uu = U-axis wind speed (m/s)
±vv.vv = V-axis wind speed (m/s)
ss = Status code
* = Asterisk (ASCII 42)
cc = Checksum
= Carriage return (ASCII 13)
The CHECKSUM is the two-character printable hexadecimal value
generated by taking the exclusive-or of all characters up to the
asterisk. The STATUS CODE will show a non-zero value only when
the sensor cannot acquire sufficient samples or a measurement
error has occurred.
5.3.3 ASCII POLLED
ASCII POLLED format is the same as ASCII but sends data only
when polled. The sensor stays in low power mode until polled. The
polling command is Ma! where 'a' is the sensor address. The default
address is '0' (ASCII 48).
5.3.4 NMEA
NMEA format provides continuous wind measurements in standard
NMEA marine sentences at 4800 baud using the RS-485 output con-
nections. Output is sent once per second. The output data may be
used with the YOUNG Model 06206 Marine Wind Tracker or other
NMEA-capable device.
NMEA FORMAT
$WIMWV,ddd,R,www.w,N,A*cc
where
ddd = Wind direction (degrees)
www.w = Wind speed (knots)
* = Asterisk (ASCII 42)
cc = Checksum
= Carriage return, line feed (ASCII 13, 10)
The CHECKSUM is the two-character printable hexadecimal value
generated by taking the exclusive-or of all characters between '$'
and '*'.
5.3.5 SDI-12 CONT
SDI-12 CONT makes continuous wind measurements that may be
retrieved with SDI-12 R, M, and C commands. With R commands,
the sensor responds by sending measurement data. With M and C
commands, the sensor responds with an acknowledgement show-
ing zero seconds measurement delay. No service request is sent.
Data may be retrieved immediately after an M or C command with
a D command.
If an R, M, or C command includes the CRC designator, retrieved
data will contain an SDI-12 CRC checksum.
SDI-12 SENSOR
COMMAND RESPONSE
aR0! a+www.w+ddd
aR1! a±uu.uu±vv.vv
aRC0! a+www.w+ddd
aRC1! a±uu.uu±vv.vv
aM! a0002
aM1! a0002
aMC! a0002
aMC1! a0002
aC! a00002
aC1! a00002
aCC! a00002
aCC1! a00002
aD0! a+www.w+ddd
a±uu.uu±vv.vv
where:
a = Sensor address
ddd = Wind direction (degrees)
www.w = Wind speed (selected units)
±uu.uu = U-axis wind speed (m/s)
±vv.vv = V-axis wind speed (m/s)
= CRC checksum (only where requested)
= Carriage return, line feed (ASCII 13, 10)
5.3.6 SDI-12 STANDBY
SDI-12 STANDBY makes wind measurements only when polled with
an M or C command. The sensor responds with an acknowledge-
ment indicating that the data will be ready in one second. With M
commands, the sensor sends a service request as soon as data are
ready. Data are retrieved with D commands. If the M or C command
includes a CRC designator, retrieved data will include a CRC check-
sum. After each measurement cycle, the sensor goes into ultra-low
power (320 uA) standby. Set Damping Factor (see 6.4.9) to 0 when
using SDI-12 STANDBY.
SDI-12 SENSOR
COMMAND RESPONSE
aM! a0012
aM1! a0012
aMC! a0012
aMC1! a0012
aC! a00102
aC1! a00102
aCC! a00102
aCC1! a00102