AML Oceanographic Micro SVT User manual

User Manual for AML Oceanographic’s Micro SVT Sensor
Micro SVT Sensor
______________
User's Manual
Version 1.21
Oct. 2004

User Manual for AML Oceanographic’s Micro SVT Sensor
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TABLE OF CONTENTS
TABLE OF CONTENTS......................................................................................................................2
1 INTRODUCTION ....................................................................................................................4
1.1 The Instrument..............................................................................................................4
1.2 The User........................................................................................................................5
2 STANDARD SPECIFICATIONS ...........................................................................................6
3 DESCRIPTION.........................................................................................................................8
3.1 Functional Description .................................................................................................8
4 PREPARATION FOR USE .....................................................................................................9
4.1 Inspecting the Instrument .............................................................................................9
4.2 Connection to a Computer ...........................................................................................9
4.3 Powering the Micro SVT Sensor ...............................................................................10
4.3.1 External Power...............................................................................................10
4.3.2 Micro SVT logging option.............................................................................10
4.3.2.1 Micro Battery Pack.........................................................................11
4.4 Software Setup............................................................................................................11
5 COMMUNICATIONS ...........................................................................................................12
5.1 RS-232 ASCII Communications................................................................................12
5.1.1 Standard Output Data format.........................................................................12
5.1.1.1 Header Output ................................................................................12
5.1.1.2 Real Output Mode..........................................................................12
5.1.1.3 Raw Output Mode..........................................................................13
5.1.2 Command Summary......................................................................................13
5.1.3 Advanced Commands...................................................................................16
5.1.3.1 Display commands .........................................................................16
5.1.3.2 Set commands ................................................................................16
5.1.3.3 Set scan options..............................................................................19
5.1.3.4 Analog board commands ...............................................................20
5.1.3.5 Set startup options ..........................................................................20
5.1.3.6 Accessing the calibration coefficients............................................22
5.1.3.7 Editing the Calibration Coefficients ..............................................23
5.1.3 Logging data...................................................................................................26
5.1.4 Using Integrated System Software (ISS).......................................................26
5.1.5 Using SmartTalk ............................................................................................26
5.1.6 Using a Terminal Emulation Program...........................................................26
6 PRECAUTIONS AND TROUBLESHOOTING GUIDE.....................................................28
6.1 Precautions..................................................................................................................28
6.1.1 Sound Velocity Sensor Precautions...............................................................28
6.1.2 Optional Sensor Precautions..........................................................................28
6.2 Sensor Interactions .....................................................................................................28
6.2.1 Electrical Interference ....................................................................................29
6.2.2 Acoustic Interference .....................................................................................29
6.2.3 Magnetic Interference ....................................................................................29
6.2.4 Radio Interference..........................................................................................29
6.3 Troubleshooting Guide...............................................................................................30

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7 MAINTENANCE ...................................................................................................................33
7.1 General Maintenance..................................................................................................33
7.2 Replacing the batteries ...............................................................................................33
7.2.1 Battery considerations for the Micro SVT ....................................................34
7.2.2 Recommended Battery rating for the Micro SVT.........................................34
7.2.3 Battery dimensions.........................................................................................34
7.2.4 Voltage capacity.............................................................................................34
7.2.5 Current Capacity ............................................................................................34
7.2.6 Maximum Current sourcing capabilities .......................................................35
8 CALIBRATION......................................................................................................................36
8.1 Sound Velocity ...........................................................................................................36
8.2 Temperature................................................................................................................36
9 WARRANTY .........................................................................................................................37
APPENDIX ‘A’: “ Drawings ” ..........................................................................................................38
APPENDIX ‘B’: “ Using Hyperterminal ”........................................................................................39
B.1 Using Hyperterminal ..................................................................................................39
APPENDIX ‘C’: “ Using PROCOMM ” ..........................................................................................41
C.1 Installing PROCOMM ...............................................................................................41
C.2 Using PROCOMM.....................................................................................................41
APPENDIX ‘D’: “ Quick Guide ” .....................................................................................................43

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1 INTRODUCTION
This manual describes the AML Oceanographic Micro SVT Sensor. If additional items
such as sensors or software are used in conjunction with the Micro SVT Sensor the
manuals for these items should also be consulted. Examples of additional manuals
commonly supplied are:
SmartTalk software manual
Transmissometer sensor manual
Dissolved oxygen sensor manual
This manual covers the standard specifications, operation, use, communication,
troubleshooting, and maintenance of the Micro SVT Sensor. In addition, appendices at
the back of the manual detail any unique configurations for the instrument. Unique
configurations include such things as calibration coefficients, additional sensors, custom
communication formats and custom wiring configurations. Also included in Appendix G
is a quick reference guide that describes the basic operating procedures on one sheet for
ease of use in the field.
1.1 THE INSTRUMENT
Figure 1.1: Micro SVT with optional 85ms temperature sensor
The standard Micro SVT Sensor is a two parameter, self contained, intelligent sensor. The
basic configuration includes the following:
sound velocity sensor and electronics
temperature sensor and electronics
communications electronics
data logger electronics
waterproof pressure case
connector cable
The exact configuration of the instrument is detailed in Appendix A.
The sound velocity sensor is a short path length, Time of Flight, proprietary design which
offers fast response times and extremely low thermal hysteresis. The signal conditioning
electronics feature thermal compensation, ratio metric A/D conversion to provide accurate
and stable operation over the operating range. The sound velocity sensor uses a dedicated
RISC microprocessor to control the sensor excitation and communicate with the data logger
electronics. The sound velocity sensor is capacitively coupled to the water to reduce noise.
The temperature sensor is a precision, aged thermistor within a Beryllium Copper (BeCu)

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capillary tube to eliminate pressure effects while still allowing fast time response. The
temperature sensor uses a dedicated RISC microprocessor to control the sensor excitation
and communicate with the data logger electronics.
The data logger and power control electronics use a RISC microprocessor running at 19.6
MHz to control the sampling and power as well as to communicate with the sensors and
communications interface board.
The communications interface board is normally an RS-232C board. Optional
communication boards include RS-485 and TTL. Through the communications board, the
instrument will on power up, automatically detect baud rates from 2400 to 38400 baud. The
baud rate is automatically determined when the sensor receives an <ENTER> or <RET>.
The data output may be configured to display either unprocessed integers, or computed
engineering values. The Micro SVT Sensor has the option of sampling on command or
monitoring continuously with programmable sampling rates. The latter is not available with
the binary protocol. The RS-485 binary protocol option allows the instruments to be
individually addressed permitting multiple instruments to be daisy-chained together.
1.2 THE USER
This manual has been written with the following assumptions:
• The user has had some exposure to MS Windows compatible computers, and is
moderately computer literate with a working knowledge of computer operation and
terminology.
• The user is familiar with the operation and function of standard communications packages.
While it is possible to operate the Micro SVT Sensor without these qualifications, some
computer experience will greatly assist the user to pass through the learning curve more
rapidly.

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2 STANDARD SPECIFICATIONS
Note: If the instrument has a custom configuration the additional specifications will be
listed in Appendix A.
Sound Velocity: Time of Flight
Range: 1375 - 1600 m/s
Accuracy: 0.05 m/s from 1400 to 1550 m/s
Resolution: 0.01 m/s
Time constant: 40 ms
Temperature Sensor: Precision aged thermistor in beryllium copper housing
Accuracy: ±0.005ºC
Resolution: 0.001ºC
Time constant: 225 ms (optional 85 ms)
Output format:
Standard: RS-232C autobaud communications
Baud rate: 2400 to 38400, 8 data bits, no parity, 1 stop bit.
Data type: ASCII text
Optional: RS-485 autobaud communications
Baud rate: 2400 to 38400 baud, 8 data, no parity, 1 stop bit.
Data type: Addressable binary network format
Sample Rate: On command or continuous.
Continuous has programmable sampling rates from 25 scans /
second to 1 scan per day.
Power:
Standard: External power
Range: 8 to 16 volts D.C.
Nominal: 12 volts D.C.
Current: 100 mA
(electronics are galvanically isolated from the water)
Memory:
Standard: No memory
Options: 16, 24, 32 and 64 Mbytes
Pressure Housing:
Material: acetal (standard)
Max Pressure: 500 meters
Optional: T-316 Stainless steel (optional)
Max Pressure: 4500 meters
Dimensions: 50.3 mm (1.98 in) Ø

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269 mm (10.6 in)
Weight: 382 g (0.84 pounds) in air for Acetal
10 g (0.02 pounds) in water for Acetal
Environment: operating: -2 to 40ºC (28 to 104ºF)
storage: -40 to 60ºC (-40 to 140ºF)
Connectors:
Bulkhead connector: IMPULSE
tm
MCBH-8FS with 24 AWG
Dummy plug: IMPULSE
tm
MCDC-8-MP
Shorting plug: IMPULSE
tm
MCDC-8-MP/S, pins 6 and 7 are shorted,
molded red
Com cable connector: IMPULSE
tm
PMCIL-8MP, pins 6,7 and 8 are shorted, 2
meter cable length, 22 AWG with DB-25
connector
Retainer ring: IMPULSE
tm
DLSMC-F
Materials: Stainless Steel, neoprene, polyurethane, acetal

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3 DESCRIPTION
3.1 FUNCTIONAL DESCRIPTION
The Micro SVT Sensor has two separate sensors, refer to figure 3.1, each of which
responds to a specific property of the water environment. The sound velocity sensor
measures the transit time of an acoustic pulse across a fixed distance. The temperature
sensor responds to the ambient temperature by passing a very small constant current
through the thermistor junction and measuring the resulting voltage developed across the
junction. The voltage is inversely proportional to the ambient temperature.
SV. Digital
Electronics
SV. Analog
Electronics
T. Digital T. Analog
Electronics Electronics
Power
Additional Sensor Channels
Data
Logger
+
Control
Power
Electronics
Signal Bus
Interface
Electronics
- RS 485
- RS 232
- TTL
Power
Signal
Optional
Battery Pack
Power
Signal
Power
SV
Temp'
Sensor
Sensor
Figure 3-1 Micro SVT Sensor Block Diagram
Each sensor requires an excitation signal and synchronous sampling of the sensor
output voltage. The sound velocity sensor also incorporates thermal compensation. The
output voltage must be converted to a digital signal (raw output) and then the calibration
coefficients must be applied to calculate the output in engineering units. All of these
requirements are controlled by a dedicated microprocessor for each sensor. Each sensor
has a dedicated electronics board to provide this functionality. Each board is composed
of an analog section and a digital section. Refer to figure 3.1.
All of the sensor boards, including any additional sensors, plug into the data logger board.
The data logger has a common signal bus for communicating with the sensor boards and
individually controlled power supplies to each of the primary sensors. A microprocessor
on the data logger board controls all the communications and power to the sensors,
collates the sensor data with a date/time stamp and supply voltage, stores the data to flash
memory if required, and outputs the data to the external world via the communications
board.
The communications board converts the incoming commands from, and the outgoing data
to, the chosen external communications format. The standard external format is RS-232C
ASCII, which is also the standard serial communications protocol for personal computers.

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4 PREPARATION FOR USE
4.1 INSPECTING THE INSTRUMENT
At AML we do our best to package our instrumentation to avoid damage during shipping,
as should the user. However accidents do happen, so an inspection of the Micro SVT
Sensor before each use will assist in spotting problems that could lead to inaccurate data or
possible failure. Examine the outside of the shipping case for evidence of heavy impacts
during transport. If signs of damage are visible continue with the inspection as follows and
notify the carrier and the factory of any damage found. Check that the communications and
power connector is not loose and that there is no dirt or grit in the connector(s). Examine
the cable for cuts or wear and check the connector ends for visible damage. Check for a
cracked or chipped sound velocity sensor, as this will change the calibration of the sensor.
Check the temperature probe for signs of damage to the capillary tube.
4.2 CONNECTION TO A COMPUTER
The user communicates with the Micro SVT Sensor via any IBM or compatible computer
or data collection device. An AML supplied data cable will link the two. Refer to the
wiring diagram in appendix C. At one end of the cable is a DB25 or DB9 female connector
that plugs into the computer's serial port and at the other end is an 8 pin plug that is inserted
into the communications port of the Micro SVT Sensor. When this connection has been
made and 12 volts applied, the instrument is powered up and ready to communicate with the
computer.
WARNING:
A plug or cable must be installed in the connector at all times when the instrument is
immersed in water. Failure to do so will cause corrosion to the connectors and may
cause water damage in the electronics housing.

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4.3 POWERING THE MICRO SVT SENSOR
4.3.1 External Power
The Micro SVT Sensor is normally powered externally via the communications cable. Refer
to the wiring diagram in Appendix C. If an AML data cable is used attach the red wire to
the positive side of the power supply and the black wire to ground. The power should be a
DC voltage between 8 and 16 volts, measured at the instrument. The instrument has reverse
voltage protection but the instrument will not function if the power leads are connected with
reverse polarity.
Figure 4.3.1 Micro instrument connected to an external power source
4.3.2 Micro SVT logging option
If the Micro SVT has been purchased with the logging option it will be equipped with
internal memory and an external battery pack. Refer to the wiring diagram in Appendix
C. If the battery pack is used, the instrument is connected to either connector on the battery
pack with an interconnect cable. The remaining connector on the battery pack is then
connected to the data/power cable, which is connected to the computer. For logging data
when not connected to the computer the red shorting plug must be inserted into the battery
pack to turn the power on to the instrument. Power for the Micro SVT sensor is turned off
if the there is no shorting plug or data/power cable plugged in to the battery pack.
Figure 4.3.2 Micro instrument with battery pack and external sensor connected to an external power
supply

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4.3.2.1 Micro Battery Pack
Figure 4.3.2.1 The Battery pack
The replacement batteries should be three, good quality, C size, lithium, 3.6 volt batteries.
Saft, LSH 14, C cell, 3.6 volt, lithium batteries are recommended. For more details on
battery recommendations refer to section 7.2 .
Insert all three batteries into the brass housing positive end first. Replace the battery cap on
the brass housing.
Check the O-ring seals. The O-rings should be clean, have no nicks, and should be lightly
greased. Slide the battery assembly back into the pressure case and screw down the
retaining ring.
4.4 SOFTWARE SETUP
If SmartTalk or ISS software has been supplied with the instrument refer to the appropriate
manual for the installation and configuration of these programs. Both of these programs are
supplied with Install Shield to simplify installation.
If a terminal emulation program such as Hyperterminal (Windows) or Procomm (DOS) is to
be used launch the program. Select the appropriate com port (to which the instrument is
connected), set the communications format to 8 bits, no parity, 1 stop bit and select a baud
rate between 2400 and 38400 baud. Apply power to the instrument and press the <enter>
key. The standard Micro SVT Sensor will respond with its header information. Note that
some units may be configured for custom outputs and may not respond with a header. This
header identifies the sensor type, serial number and firmware version. The sensor is then
ready to accept commands. If the sensor does not respond refer to the trouble-shooting
guide in section 6.3 or the instrument configuration in Appendix A.
The command summary for communicating with the instrument is given in section 5.

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5 COMMUNICATIONS
5.1 RS-232 ASCII COMMUNICATIONS
5.1.1 Standard Output Data format
The standard data format is for RS-232C ASCII based sensors. Custom data outputs and
formats are listed in appendix A. The Micro SVT Sensor can output data in Raw or Real
modes. The mode can be changed by supplying the appropriate command. Refer to
section 5.1.2 for commands.
5.1.1.1 Header Output
When a standard Micro SVT Sensor is first powered up it monitors the communications
line. If a data cable is connected the instrument will monitor the signal line for a carriage
return/line feed (i.e. the <enter> key) from the external computer. The instrument
automatically determines the baud rate and configures itself to match. The instrument
then responds with the header information. The header identifies the sensor type,
firmware version and serial number of the instrument.
Example header:
Micro SVT Sensor V1.0 SN:4426-SVT
Copyright 2003, AML Oceanographic
5.1.1.2 Real Output Mode
The Real mode outputs only the final calculations of date/time and sensor readings in
engineering units. The output is sent as space delimited ASCII characters in the
following format:
Date (Month/Day/Year) Time (hh:mm:ss:and hundredths of seconds), sound velocity (in
m/s), temperature (in °C) and a carriage return/line feed (end of scan).
Example scan:
05/14/03 14:23:06:02 1523.74 11.793
The above example reads
Date: Month/Day/Year
Time of scan: 2:23 pm and 6.02 seconds
Sound velocity: 1523.74 m/s
Temperaure: 11.793°C
Note: a positive sign is not displayed for positive temperatures.

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5.1.1.3 Raw Output Mode
The Raw mode shows the outputs from the analog to digital converters for each sensor.
No compensation or manipulation of the data is performed in Raw mode. Refer to section
8 and appendix B to convert the raw data values to engineering data. The raw counts for Nl,
Nsv, Nh, and Nt are integers between 0 and 65535. The output is sent as space delimited
ASCII characters in the following format:
Date(Month/Day/Year) Time (hh:mm:ss:and hundredths of seconds), Nl, Nsv, Nh, Nt and
a carriage return/line feed (end of scan).
Example scan: 04/14/03 14:23:08.06 15283 22544 61897 13487
5.1.2 Command Summary
All commands are in the form of standard English words. Commands can be entered in
upper or lower case letters followed by an <ENTER>. The minimum letters of the
command that the instrument will recognize are enclosed in brackets.
Command: RAW [R]
This command will set the instrument to output RAW uncorrected data when using the
MONITOR or SCAN commands.
Command: REAL [RE]
This command will set the instrument to output Real corrected engineering data when using
the MONITOR or SCAN commands.
Command: / [/]
This command is used to toggle RAW and REAL modes of operation.
Command: SCAN [S]
This command outputs one scan of data.
Command: MONITOR [M]
This command sets the instrument to output multiple scans continuously at the scan rate set
by the “SET” command. To discontinue the monitor command the break key or the space
bar can be depressed. Note: this command is not available with the binary format
instruments.

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Command: SET [SE] SAMPLE RATE [S]
This command sets the rate at which the instrument will take samples (or scans). The
sample rate is in the form of a number followed by the time units. The allowable time units
are listed below:
CONTINUOUS [C]
/SECONDS {/S]
SECONDS [S]
MINUTES [M]
HOURS [H]
The following examples demonstrate some of the possible permutations of this command.
SET SAMPLE 6 HOUR This will set the sample rate for one sample every 6 hours.
SE SA 30 SEC This will set the sample rate for one sample every 30
seconds.
SET S 5 S This will set the sample rate for one sample every 5 seconds.
SE S CONTINUOUS This sets the sample rate at the maximum of 25 scans per
second.
Command: TIME [T]
This command sets the real time clock in the instrument. This command uses the 24 hour
clock with a format of hh:mm:ss.hh
Example:
TIME 13:44:12
Command: DATE [DA]
This command sets the date using the format mm/dd/yy.
Example:
DATE 03/11/03 (March 11, 2003)
Command: VERSION [V]
This command displays the current version of the firmware, instrument type and the serial
number of the instrument
Command: DIS S
This command displays the current scan rate.
Example:
>DIS S sample rate is 1 seconds

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Command: DUMP
This command dumps the instrument’s logged data from memory. The data will be
dumped as REAL data and is in the following format.
Example:
>DUMP [ret]
New Cast
03/05/03 14:23:06:02 1523.74 11.793
03/05/03 14:23:07:02 1523.75 10.232
03/05/03 14:23:08:02 1523.77 09.567
03/05/03 14:23:09:02 1523.78 08.573
>
Command: INIT
This command clears the instruments memory.

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5.1.3 Advanced Commands
5.1.3.1 Display commands
Command: DIS SCAN [D SC]
This command will display the current scan options.
Example:
>dis scan
Scan delay is 100
Display time: yes
Display date: no
Command: DIS STARTUP [D ST]
This command will display the current startup options.
Example:
>dis startup
Logging timeout is disabled
Startup delay is 0
Header is displayed
Start up in prompt mode
Characters reception is enabled
Command: DIS MEMORY [D M]
This command will display the current memory status.
Example:
>dis m
Memory is not installed
Or if there is memory
>dis m
Memory is 005.00% used
NOTE: Use the VER command to display total memory available to the system.
5.1.3.2 Set commands
Command: SET SN nnnn
This command sets the serial number of the instrument. To display the instruments serial
number use the VER command.
Example:
>set sn 1234
To display the serial number,
>ver

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SVT Micro Sensor V2.01 SN:1234-SVT
Copyright(C) 2003, AML Oceanographic
32MB of Memory
Warning: Changing the instruments serial number will adversely effect the
operation of Smart Talk or ISS software.
Command: SET DETECT ab [SE D ab]
Where
a = a Hex number between 0-F
b = a Hex number between 0-F
This command sets the detection mode of the instrument on power up.
The DETECT command can be used to set the Micro SVT to start up in the Auto baud
mode or to set the instrument to default to a specific baud rate at power up.
The ‘a’ value represents how many times the Micro SVT will try to determine the baud
rate (when the enter key is pressed) before it defaults to the baud rate set by the value of
‘b’. If a = 0 the Micro SVT will not auto baud and will default to the baud rate specified
by the value of ‘b” at each power up.
Specific values of ‘b’ and the corresponding baud rates are outlined in the table below.
b value Baud rate
1 1200
21200
32400
44800
59600
619200
738400
Example 1:
>set detect a7
In the above example, the Micro SVT will try 10 times to auto baud. If the
instrument is not able to establish a baud rate, it will default to 38400 baud.
Example 2:
>set detect 05
In the above example, the Micro SVT will not try to auto baud, but will simply
default to 9600 baud on power up.
Command: SET DEFAULT [SE DEF]
This sets the instrument to its original factory default settings.

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Command: SET RXOFF
This command will disable the reception of characters at the next power up.
The RXOFF command will instruct the Micro SVT to ignore any communications from
the computer and is used to assure spurious signals due to external noise or long cable
lengths do not interrupt the Micro SVT.
On power up, the Micro SVT will wait for 200ms before entering into the RXOFF mode
and during this time sending a carriage return will disable the RXOFF features.
To exit the RXOFF mode, hold down the carriage return key and power up the unit, then
from the prompt, issue the SET RXON command.
Command: SET RXON
Enable reception of characters at the next power up.
Command: SET TIMEOUT nn [SE T nn]
Where ‘nn’ is time in minutes and represents an integer value from 0 to 30
This command instructs the Micro SVT to enter a logging mode after a specified time
interval has passed in which the instrument has been idle. A time interval of 0 will
deactivate the command. Use the DIS ST command to view the timeout value.
Example:
>set timeout 10
The above example will instruct the Micro SVT to enter the logging mode if it sits
idle at the command prompt for more than ten minutes.
>set timeout 0 (disable the timeout feature)
Note: Power the Micro SVT off, then on to exit the logging mode.

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5.1.3.3 Set scan options
Command: SET SCAN DELAY nnn [SE SC D nnn]
The scan delay is defined as the time between the sensor board power up and a scan of
data. The time (nnn) is entered in 0.2-second intervals. Maximum scan delay is 255, or 51
seconds.
This command is used for sensors that have a slower power up response time.
Example:
>set scan delay 20 (sets the scan delay to 4 seconds)
In the above example, the Micro SVT would power up the sensor boards, wait 4
seconds then take a scan of data.
Micro SVT power up timing diagram
Command: SET SCAN TIME [SE SC T]
This command enables the displaying of time during a data scan.
Command: SET SCAN NOTIME [SE SC NOT]
This command disables the displaying of time during a data scan.
Command: SET SCAN DATE [SE SC DA]
This command enables the displaying the date during a data scan.
Command: SET SCAN NODATE [SE SC NOD]
This command disables the displaying of the date during a data scan.

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5.1.3.4 Analog board commands
The Micro SVT can be configured for two additional analog channels if the optional Micro
analog board is installed. These channels may be used to incorporate additional sensors such as
Ph, Do2 or any other sensor outputting a voltage. When the Micro SVT is equipped with an
analog board, the following commands can be used to configure the extra channels.
Note: Data will not be logged from an analog channel that is turned off.
Please refer to section 1.2 for information on the Micro SVT’s channel configuration.
Command: SET ANALOG ON [SE A O]
This command enables the displaying of the analog channel/s.
Command: SET ANALOG OFF [SE A OF]
This command disables the displaying of the analog channel/s.
Data from the analog board will not be logged.
Command: SET ANALOG 1 [SE A 1]
This command will enable the displaying of analog channel #1 when the analog board has
been enabled with the SET ANALOGON command.
Analog channel #2 data will not be displayed or logged.
Command: SET ANALOG 2 [SE A 2]
This command will enable the displaying of analog channels #1 and #2 when the analog
board has been enabled with the SET ANALOGON command.
5.1.3.5 Set startup options
Command: SET STARTUP DELAY nnn [SE ST D nnn]
The Startup Delay time is defined as the time difference between the logger board
powered up, and when the sensor boards are powered up. The time (nnn) is entered in
0.02-second intervals. Maximum startup delay is 255, or 5 seconds.
This command may be used for a “gentle power on”, to power up the instrument in stages
thus avoiding large power up current spikes that may result when using long cables or
batteries with high internal resistances.
Example:
>set startup delay 200 (set the startup delay to 4 seconds)
In the above example, 4 seconds after the Micro SVT is powered up the
sensor boards will be powered up.