Sensorsoft

Sensorsoft Thermometer
User Manual

Models ST6105J, ST6105C and ST6154J
Manual P/N 071-0014 Rev 10
April 4, 2014
Copyright © 1999-2014 Sensorsoft Corporation, All rights reserved.
Sensorsoft and Soft Thermometer are trademarks of Sensorsoft Corporation.
Table of Contents
Overview.......................................................................................................................................... 4
About this Manual............................................................................................................................ 4
Installing the Sensorsoft Thermometer ........................................................................................... 5
Choosing an Installation Location................................................................................................ 5
Connecting the Sensorsoft Thermometer to a serial port............................................................ 5
ST6105C Sensorsoft Thermometer Specifications ......................................................................... 7
ST6105J Sensorsoft Thermometer Specifications.......................................................................... 8
ST6154J Sensorsoft Thermometer Specifications.......................................................................... 9
Resolution, Accuracy and Calibration ........................................................................................... 10
Avoid making invalid judgements or comparisons..................................................................... 10
Use the proper instrument and method to make comparisons.................................................. 10
What to do, if you believe the Sensorsoft device is reading incorrectly .................................... 11
Making extension cables for C-Suffix Sensorsoft Devices............................................................ 12
Making communication cables for J-Suffix Sensorsoft Devices.................................................... 13
Writing programs for the Sensorsoft Thermometer....................................................................... 16
Sending commands to the Sensorsoft Thermometer ................................................................ 16
Receiving responses from the Sensorsoft Thermometer .......................................................... 18
Converting DATA-byte(s) to temperature readings ................................................................... 19
Reading the Sensorsoft ID Record ............................................................................................ 21
Getting Help................................................................................................................................... 23
Limited Warranty........................................................................................................................ 23
Technical Support ...................................................................................................................... 23
30 Day Money Back Guarantee................................................................................................. 23
Returns....................................................................................................................................... 23
FCC Compliance and Advisory Statement.................................................................................... 24
Sensorsoft Thermometer User Manual
Overview
The ST6105C, ST6105J and ST6154J Soft Thermometers are RS232 compatible serial devices
based on the Sensorsoft Device Protocol. The ST6105C and ST6105J have a built-in temperature
sensor and are intended for applications where the customer needs to monitor or measure
temperature in rooms or warehouses. The ST6154J has an external probe and is intended for
applications where the temperature probe can be located outdoors, immersed in a liquid or slipped
into hard to reach places.
Sensorsoft devices offer the following benefits over other RS232 serial devices:
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Powered from the serial port (no external power or battery required)
CRC error detection (detects transmission errors and improves reliability)
Virtually unlimited cable lengths (1000 ft)
Plug and go operation (little or no user configuration required)
About this Manual
The Sensorsoft Thermometer may also be referred to as a Soft Thermometer, Sensorsoft device or
SSD (Sensorsoft Soft Device) throughout this manual.
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Sensorsoft Thermometer User Manual
Installing the Sensorsoft Thermometer
Installation of the Sensorsoft Thermometer is composed of the following steps:



Choosing an Installation Location
Connecting the Sensorsoft Thermometer to a serial port
Starting the Sensorsoft software. Please refer to the specific software manual that applies to
your installation.
Choosing an Installation Location
Model ST6105C and ST6105J
Locate these Sensorsoft Thermometer close to the equipment or airflow you are monitoring.
Since the ST6105C/J Sensorsoft Thermometer is not waterproof or weatherproof, keep the
following rules in mind:



Keep the Sensorsoft Thermometer housing out of contact with direct sunlight, UV exposure
and dripping water.
Protect the Sensorsoft Thermometer from high traffic areas that could wear/damage the
housing or cable.
Never allow the plastic housing of the Sensorsoft Thermometer to come into contact with
harsh chemicals or cleaning agents. If it needs to be cleaned, do so with a damp cloth or
vacuum cleaner.
Use a Velcro fastener (P/N F1000 or F1001) to affix the Sensorsoft Thermometer to a stable
surface.
Model ST6154J
Since this Sensorsoft Thermometer has an external stainless steel probe, you may expose the
probe portion to liquids or outdoor environments. However the same restrictions apply to main
plastic housing as does with the ST6105C/J above.
Connecting the Sensorsoft Thermometer to a serial port
If you have a ST6105C (C-Suffix) Sensorsoft Thermometer, plug its molded DB-9F connector
into an available RS232 serial port connector (DB-9M) on your computer or device server.
If you have an ST6105J or ST6154J (J-Suffix) Sensorsoft Thermometer, use the appropriate
C200X cable to connect this device to your computer or device server. Please refer to the
Sensorsoft price list for available types.
If you intend to make your own custom cable for a J-Suffix Sensorsoft device, please refer to
Making communication cables for J-Suffix Sensorsoft Devices.
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Sensorsoft Thermometer User Manual
If you are connecting a Sensorsoft Thermometer to a device server please be sure to configure the
port as follows:

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1200 bps, 8 bits, no parity, 1 stop bit
Turn off autobaud
Flow control set to none
Non-telnet binary (raw) transfer mode
Assert RTS and DTR always
Refer to your device server’s documentation for more details on the above.
Note the physical or COM port number where you plugged the cable into your computer or
device server. If the Sensorsoft Thermometer is being plugged into a Windows based computer
that has only one COM port, the port number is usually COM1.
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Sensorsoft Thermometer User Manual
ST6105C Sensorsoft Thermometer Specifications
Measurement Range: -40 º C to +60 º C (-40 º F to +140 º F)
Resolution or precision: 0.1 º C (0.18 º F) and 0.5 º C (0.9 º F)
Accuracy: +/- 0.5 º C (+/- 0.9 º F) over 0 º C to +60 º C (32 º to 140 º F) and
+/- 1 º C (1.8 º F) over remainder of temperature range
Calibration: Calibrated at the factory. Re-calibration in the field is not possible, but sensor can
be replaced. See Sensor type below for replacement part number.
Maximum measurement rate: one reading every second
Housing Dimensions: 8 cm (3.1") x 4 cm (1.6") x 2 cm (0.8")
Housing Material: injection molded ABS thermoplastic
Housing Color: light gray
Sensor type: semiconductor, internal (Dallas Semiconductor DS18S20)
Communications cable: integrated 6 m (20 ft.) cable with DB-9F (female) mini D-SUB
connector
Power source: Port-powered (RTS and DTR, both asserted).
Power supply current drain: < 10 mA
Communications Interface: RS232C using TX,RX,RTS,DTR and GND. One device per serial
port.
Maximum extension cable length: 305 m (1000 ft.) using recommended cable type. Low
capacitance shielded cable or UTP is recommended.
Communications Protocol: Sensorsoft Device Protocol, Version 2.0
Error control: 16 bit CRC (cyclic redundancy checking) for detection of communication errors
between the device and host computer.
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Sensorsoft Thermometer User Manual
ST6105J Sensorsoft Thermometer Specifications
Measurement Range: -40 º C to +60 º C (-40 º F to +140 º F)
Resolution or precision: 0.1 º C (0.18 º F) and 0.5 º C (0.9 º F)
Accuracy: +/- 0.5 º C (+/- 0.9 º F) over 0 º C to +60 º C (32 º to 140 º F) and
+/- 1 º C (1.8 º F) over remainder of temperature range
Calibration: Calibrated at the factory. Re-calibration in the field is not possible, but sensor can
be replaced. See Sensor type below for replacement part number.
Maximum measurement rate: one reading every second
Housing Dimensions: 8 cm (3.1") x 4 cm (1.6") x 2 cm (0.8")
Housing Material: injection molded ABS thermoplastic
Housing Colour: light gray
Sensor type: semiconductor, internal (Dallas Semiconductor DS18S20)
Communications connector: 8 position modular jack, (accepts 8 position plug RJ45)
Power source: Port-powered (RTS and DTR, both asserted) or via External DC power connector
Power supply current drain: < 10 mA
External DC power connector: 2.1 mm power jack, automatic polarity correction and overvoltage protection.
External power supply voltage: 6.0 - 12.0 VDC
Communications Interface: RS232C using TX,RX,RTS,DTR and GND. One device per serial
port.
Maximum communications cable length: 305 m (1000 ft.) using recommended cable type. Low
capacitance shielded cable or UTP is recommended.
Communications Protocol: Sensorsoft Device Protocol, Version 2.0
Error control: 16 bit CRC (cyclic redundancy checking) for detection of communication errors
between the device and host computer.
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Sensorsoft Thermometer User Manual
ST6154J Sensorsoft Thermometer Specifications
Probe measurement range: -55 º C to +125 º C (-67 º F to +257 º F)
Resolution or precision: 0.1 º C (0.18 º F) and 0.5 º C (0.9 º F)
Accuracy: +/- 0.5 º C (+/- 0.9 º F) over 0 º C to +70 º C (32 º to 158 º F) and
+/- 1 º C (1.8 º F) over remainder of temperature range
Calibration: Calibrated at the factory. Re-calibration in the field is not possible. Sensor probe
can be replaced if returned to the factory.
Maximum measurement rate: one reading every second
Probe dimensions: 20.3 cm (8") long, 6 mm (1/4") diameter, stainless steel probe with 1.2 m (4
ft.) long, high-temp silicone rubber cable.
Sensor type: semiconductor (Dallas Semiconductor DS18S20)
Housing Dimensions: 8 cm (3.1") x 4 cm (1.6") x 2 cm (0.8")
Housing Material: injection molded ABS thermoplastic
Housing Color: light gray
Housing operating temperature: -40 º C to +60 º C (-40 º F to +140 º F)
Communications connector: 8 position modular jack, (accepts 8 position plug RJ45)
Power source: Port-powered (RTS and DTR, both asserted) or via External DC power connector
Power supply current drain: < 10 mA
External DC power connector: 2.1 mm power jack, automatic polarity correction and overvoltage protection.
External power supply voltage: 6.0 - 12.0 VDC
Communications Interface: RS232C using TX,RX,RTS,DTR and GND. One device per serial
port.
Maximum communications cable length: 305 m (1000 ft.) using recommended cable type. Low
capacitance shielded cable or UTP is recommended.
Communications Protocol: Sensorsoft Device Protocol, Version 2.0
Error control: 16 bit CRC (cyclic redundancy checking) for detection of communication errors
between the device and host computer.
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Sensorsoft Thermometer User Manual
Resolution, Accuracy and Calibration
The terms resolution, accuracy and calibration frequently cause misunderstanding for many
individuals who have not been trained in metrology. We endeavor here to explain these terms and
how they might affect your application of Sensorsoft devices.
Resolution or precision is the fineness of the measurement. It is usually specified in terms of the
smallest unit that can be resolved.
Accuracy is the trueness of the measurement or how close it can be to the true value (National
Standard). Accuracy is often specified as a percentage (i.e. +/- 3 % of reading), or a fixed value
(i.e. +/- 0.5 ) that the reading can vary from the true value.
Calibration is a process where accuracy is verified (and often corrected) with respect to a
standard. Calibrations are routinely carried out to certify that a device has not lost its accuracy,
linearity and stability. Calibrations can be carried out at a time interval that is required by your
industry. In many cases this is done at least once every year. When a calibration or verification
takes place, it must always be done with equipment that has significantly better accuracy and
resolution then the device under test. When a calibration is performed on a unit under test with an
instrument that is proven as traceable to the National Standards Laboratory, the unit under test is
also considered to be traceable.
Avoid making invalid judgements or comparisons
Using any of the following measurement devices or situations is unacceptable for comparing to,
or judging the accuracy of a Sensorsoft device:
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

Measurement device purchased from a hardware or drug store
Digital display on HVAC or cooling/heating equipment
Location of the active sensing element is unknown
Measurement device has its active sensing element more than one inch (2.5 cm) away from
the Sensorsoft device/probe
Measurement device has similar specifications to the Sensorsoft device
Measurement device has unknown specifications
Measurement device has not been calibrated within one year, has no calibration certificate or
is not traceable to a standard
Use the proper instrument and method to make comparisons
We recommend one of the following instruments (or equivalent) that have a recently dated
traceable calibration certificate, for judging the accuracy or stability of your Sensorsoft device:
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
Vaisala HM34 Humidity & Temperature Meter (Hand held, approx. price $500 USD)
Vaisala HMP233 Humidity & Temperature Transmitter and external probe (Wall mount,
RS232 interface, order with 115/230 VAC power supply, approx. price $1800 USD)
Vaisala HMI38/HMP35E Humidity & Temperature Data Processor and external probe (Desk
top unit, RS232 interface, approx. price $2580 USD)
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Sensorsoft Thermometer User Manual
More details about the above instruments are available on Vaisala's web site:
http://www.vaisala.com
Keep the following points in mind when assessing the accuracy or stability of your Sensorsoft
device:
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
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
Use one of the above recommended instruments (or equivalent)
Recommended instrument has had a traceable calibration within one year of current date
Sensorsoft device and the traceable instrument's probe must be exactly side by side (within
one inch of each other)
Allow sufficient time (10-20 minutes) for the Sensorsoft device and the traceable instrument
to stabilize
What to do, if you believe the Sensorsoft device is reading incorrectly
If after following the above procedure you find that the Sensorsoft device is not reading within its
stated specifications, you have two options:
a) Return the Sensorsoft device to our factory for repair or calibration. See Returns at the end of
this guide. Charges may apply if the unit is out-of-warranty or if we find no evidence that the
device is out-of-calibration.
b) If you have access to a local calibration lab you may send it there for verification or
calibration along with the Remote Watchman software. Refer to the specifications of your
Sensorsoft device to determine whether its sensor can be re-calibrated or replaced.
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Sensorsoft Thermometer User Manual
Making extension cables for C-Suffix Sensorsoft
Devices
In some applications it is not possible to use pre-assembled cables. When installing the Sensorsoft
device at a remote location it may be necessary to run cables through walls, ceiling or conduits
where connectors would get jammed. In this situation it makes sense to run the cables and then
terminate them, on-site, using hand tools. Further, if your host serial port is of the DCE type
(some multi-port serial cards) it will be necessary to make your own cables. The following details
will assist you in doing that.
A properly made cable will allow your Sensorsoft device to operate reliably over long distances.
PIN-OUT OF THE DB-9F CONNECTOR ON A C-SUFFIX SENSORSOFT DEVICE
Note: Only positions used in Sensorsoft device application are shown
Position
2
3
4
5
7
Function
TX (data to computer)
RX (data from computer)
POWER (connects to DTR on computer)
Ground
POWER (connects to RTS on computer)
The following are suggested specialized tools and parts needed to make good quality extension
cables:
Hand Tools:
AMP Crimping Tool P/N 90312-1 or 90302-1, for subminiature D pin or socket contacts
AMP PROCRIMPER P/N 58448-2, for subminiature D pin or socket contacts
AMP Insertion/Extraction Tool P/N 91285-1, for subminiature D connector contacts
Materials:
Berk-Tek UTP (Unshielded Twisted Pair) round stranded cable, P/N 540036--TP
(4 pair, 8-#24 AWG wires, category 4 or better, 75 C)
AMP DB-9 receptacle subminiature D connector (crimp-snap-in), P/N 205203-1 or -3
AMP DB-25 receptacle subminiature D connector (crimp-snap-in), P/N 205207-1 or 207463-1
AMP socket crimp contact for subminiature D connectors, P/N 1-66504-0
AMP pin crimp contact for subminiature D connectors, P/N 1-66506-0
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Sensorsoft Thermometer User Manual
Making communication cables for J-Suffix Sensorsoft Devices
In some applications it is not possible to use pre-assembled cables. When installing the Sensorsoft
device at a remote location it may be necessary to run cables through walls, ceiling or conduits
where connectors would get jammed. In this situation it makes sense to run the cables and then
terminate them, on-site, using hand tools. Further, if your host serial port is of the DCE type
(some multi-port serial cards) it will be necessary to make your own cables. The following details
will assist you in doing that.
A properly made cable will allow your Sensorsoft device to operate reliably over long cable
lengths up to 305 m (1000 ft) long. You may connect the Sensorsoft device to the port with as
little as three wires (RX,TX and GND) using inexpensive unshielded telephone wire. However
the host may need to set the number of retries high in order to overcome the effect of occasional
noise/interference and would also require the use of an external power supply at the Sensorsoft
Thermometer.
The Sensorsoft device modular jack connector uses the same UTP wire map as 10-BASE-T and
ISDN. It is therefore possible to use this type of cabling system for Sensorsoft devices.
PIN-OUT OF THE MODULAR 8 POSITION JACK/PLUG ON A SENSORSOFT DEVICE
Note: Terminal No. 1 is the terminal to the extreme left as you face the cable opening, latch tab down.
Terminal
1
2
3
4
5
6
7
8
Function
ST Receive Data
Ground
ST Transmit Data
Power +V
Ground
Ground
Power +V
Ground
UTP wire color (solid-tracer)
white-green
green
white-orange
blue
white-blue
orange
white-brown
brown
The following are suggested specialized tools and parts needed to make good quality cables:
Hand Tools:
AMP Crimping Tool P/N 1-231652-0 or 2-231652-1, for modular plugs
AMP 8 position modular die set P/N 853400-1
AMP Crimping Tool P/N 90312-1 or 90302-1, for subminiature D pin or socket contacts
AMP PROCRIMPER P/N 58448-2, for subminiature D pin or socket contacts
AMP Insertion/Extraction Tool P/N 91285-1, for subminiature D connector contacts
Materials:
Berk-Tek UTP (Unshielded Twisted Pair) round stranded cable, P/N 540036--TP
(4 pair, 8-#24 AWG wires, category 4 or better, 75 C)
AMP 8 position modular plug for round stranded wire cables, P/N 5-554169-3 (CAT4)
AMP 8 position modular plug for round stranded wire cables, P/N 5-557961-3 (CAT5)
AMP DB-9 receptacle subminiature D connector (crimp-snap-in), P/N 205203-1 or -3
AMP DB-25 receptacle subminiature D connector (crimp-snap-in), P/N 205207-1 or 207463-1
AMP socket crimp contact for subminiature D connectors, P/N 1-66504-0
AMP pin crimp contact for subminiature D connectors, P/N 1-66506-0
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Sensorsoft Thermometer User Manual
Cable P/N C2000
9 pin Serial Port to Sensorsoft Device
DB-9F to RJ45 modular plug
9 pin Port
Sensorsoft Device
3
TX
white-green
RX
1
2
RX
white-orange
TX
3
4
DTR
white-brown
POWER +V
7
7
RTS
blue
POWER +V
4
5
SIGNAL GND
green
GND
2
P/N C2000 is for use with PC’s and most other devices which have a 9 position serial
port. F indicates female/socket type connector.
Cable P/N C2001 and C2002
DTE Serial Port to Sensorsoft Device
DB-25 to RJ45 modular plug
DTE Port
Sensorsoft Device
2
TX
white-green
RX
1
3
RX
white-orange
TX
3
20
DTR
white-brown
POWER +V
7
4
RTS
blue
POWER +V
4
7
SIGNAL GND
green
GND
2
P/N C2002 is for use with Sun SPARCstation or SPARCserver serial ports A or B. The
DTE end of this cable uses a DB-25M connector. P/N C2001 is for use with PC’s which
have a DB-25 connector. The DTE end of this cable uses a DB-25F connector. M
indicates male/pin type connector. F indicates female/socket type connector.
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Sensorsoft Thermometer User Manual
Cable P/N C2012
DCE Serial Port to Sensorsoft Device
DB-25M to RJ45 modular plug
DCE Port
Sensorsoft Device
3
TX
white-green
RX
1
2
RX
white-orange
TX
3
6
DSR
white-brown
POWER +V
7
5
CTS
blue
POWER +V
4
7
SIGNAL GND
green
GND
2
P/N C2012 is for use with some multiport cards and terminal servers which have a DCE
pin-out. M indicates male/pin type connector.
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Sensorsoft Thermometer User Manual
Writing programs for the Sensorsoft Thermometer
The following describes how to write your own programs for the Sensorsoft Thermometer. This
Sensorsoft device uses a binary, packet-formatted, master-slave protocol. All data is represented
in the little endian format - least significant byte is first and the most significant byte is last.
Your host computer (master) must send commands to and receive responses back from the
Sensorsoft device (slave).
Use the following parameters when programming the serial port where the Sensorsoft device is
connected:
Bit rate:1200 bps
Bits:
8
Parity:
none
Stop bits:
1
Flow control: none
Null discard: do not strip NULL bytes
In order to make use of the port powered feature of the Sensorsoft device you must enable serial
port lines DTR and RTS when the port is opened. A delay of 1-2 seconds is required after
opening the serial port before any commands are sent to the Sensorsoft device. This delay allows
the Sensorsoft device to power-up correctly before it receives any commands and prevents
incorrect readings.
You should also be aware that the Sensorsoft device has an inter-packet retry time-out delay. This
delay is one (1) second and is encoded into the Sensorsoft device’s firmware. If your program
sends a command to the Sensorsoft device and it receives no response, your program must wait at
least one (1) second before re-sending that command. Possible reasons that a Sensorsoft device
may ignore your commands can be due to data transmission (CRC) errors or improper power-up
delay during hot plugging.
Sending commands to the Sensorsoft Thermometer
Each command packet your host sends to the Sensorsoft Thermometer must be in the following
format:
<CMD-byte> <PACKETlength-bytes> <ADDRESS-bytes> <ARGUMENT-byte> <CRC-bytes>
CMD-byte
A single byte command indicating the desired action the Sensorsoft Thermometer device should
carry out.
PACKETlength-bytes
Two bytes indicating the total length of the packet from start to finish (includes CRC bytes).
ADDRESS-bytes
The six-byte (48-bit) address of the device you are sending the command to. For RS232
Sensorsoft devices this is always decimal 1.
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Sensorsoft Thermometer User Manual
ARGUMENT-byte
The number of the Sensorsoft Thermometer's internal register you want to read or write. This byte
is required for the temperature command. This byte is not required for the status command.
CRC-bytes
A two byte (16 bit) Cyclic Redundancy Check that is calculated on the entire packet from the
CMD byte to the last ARGUMENT byte or ADDRESS byte. In the examples below, the last two
bytes in each command string are CRC bytes that were pre-calculated.
Send the following bytes to request a status reading:
<C1h><0Bh><00h><01h><00h><00h><00h><00h><00h><47h><98h>
Send the following bytes to request a temperature reading in Celsius (0.5 C resolution):
<C5h><0Ch><00h><01h><00h><00h><00h><00h><00h><01h><0Eh><49h>
Send the following bytes to request a temperature reading in Celsius (0.1 C resolution):
<C5h><0Ch><00h><01h><00h><00h><00h><00h><00h><02h><6Dh><79h>
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Sensorsoft Thermometer User Manual
Receiving responses from the Sensorsoft Thermometer
Each response packet the Sensorsoft Thermometer returns is in the following format:
<RESPONSE-byte> <PACKETlength-bytes> <DATA-byte(s)> <CRC-bytes>
RESPONSE-byte
A single byte response code indicating the type of response. Valid codes are 90 hex or 94 hex.
PACKETlength-bytes
Two bytes indicating the total length of the packet from start to finish (includes CRC bytes).
DATA-byte(s)
Most responses return additional data in the form of byte(s). In response to a temperature
command, two bytes are returned for DATA-byte(s). In response to a status command, one byte is
returned for DATA-byte(s). See SENSORSOFT DEVICE STATUS BYTE FORMAT chart.
CRC-bytes
A two byte (16 bit) Cyclic Redundancy Check. This placeholder is filled with CRC bytes
calculated by the Sensorsoft device on the entire packet from the RESPONSE byte to the last
DATA-byte. These bytes allow the host to verify the integrity of the response packet. You may
choose to use or ignore these bytes depending on your programming skill or application.
The Sensorsoft device returns a normal RESPONSE-byte (90 hex) in acknowledgement that the
previous host command was received and executed without errors. The Sensorsoft device only
acknowledges correctly received commands that have no CRC errors. If the Sensorsoft device
detects a CRC error in a received command packet, it does not respond to the command. It is
considered the job of the host to time-out and re-transmit that command packet.
When an internal problem occurs inside the Sensorsoft device it sends out an abnormal response
byte (94 hex) in response to any command from the host. If the host receives this response byte, it
must immediately read and interpret the Sensorsoft device’s status to determine the problem. See
SENSORSOFT DEVICE STATUS BYTE FORMAT chart.
The generator polynomial used for the CRC is hexadecimal 1021. The following references
provide information for readers who wish to use the CRC capability;





Calculating CRC’s by Bits and Bytes, Greg Morse, Byte Magazine, September 1986, Pg.
115-124
Implementing CRC's, Jack Crenshaw, Embedded Systems Programming Magazine, January
1992, Pg. 18-45
Technical Aspects of Data Communication, John McNamara, Digital Equipment Press 1982,
Pg. 110-122
Data and Computer Communications, 2nd edition, William Stallings, Macmillan Publishing,
Pg. 107-112
The modem reference: the complete guide to selection, installation, and applications, 2nd
edition, Michael A Banks, Brady Publishing 1991, Pg. 27-42
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Sensorsoft Thermometer User Manual
SENSORSOFT DEVICE STATUS BYTE FORMAT
BIT
0
1
2
3
4
5
6
7
NAME
Low power supply
IRQ enable
IRQ pending
Power-up
Tamper
NV option
EEPROM fail
Future use
DESCRIPTION
Voltage is unacceptable for reliable operation
N/A
N/A
Sensorsoft device just powered-up
Sensor element is disconnected or broken
N/A
N/A
N/A
A logic one condition on any of these bits indicates the condition is set or active. Otherwise they
are reset to logic zero. It is a good practice for the host to check the status of the Sensorsoft
device on a regular basis in case a bit changes state.
If bit 0 is set, this indicates that the Sensorsoft device power supply voltage is too low.
When bit 3 is set, this indicates that the Sensorsoft device has just powered-up. This bit gets reset
after the status is read.
When bit 4 is set, this indicates that the sensor element has become damaged, disconnected or is
being subjected to a high level of RFI (radio frequency interference) or EMI (electro magnetic
interference).
Bits 1,2,5,6 and 7 can be ignored, they are not used.
Converting DATA-byte(s) to temperature readings
In response to a temperature command the Sensorsoft Thermometer returns two bytes in the
DATA-byte(s) placeholder, as described below.
It is the job of the host software to convert the DATA-byte(s) to a floating-point number. It is
then possible to display readings in Celsius or Fahrenheit scale. The following procedure explains
the steps required:
1. Check the value of the most significant DATA-byte. If it is FFh the number is negative and
requires processing by steps 2,3,4 and 5. If it is 00h the number is positive and requires
processing by steps 3 and 5.
2. Invert the bits of the least significant DATA-byte, then add 1 to it.
3. Convert the least significant DATA-byte to a floating-point number.
4. Multiply the previous by -1 to get the negative result.
5. To obtain a temperature in Celsius, divide the previous result by 2. For Fahrenheit, multiply
the Celsius value by 9, divide by 5 and add 32.
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Sensorsoft Thermometer User Manual
SENSORSOFT THERMOMETER TEMPERATURE DATA-byte(s) FORMAT
Temperature
+ 125 °C
+ 85 °C
+ 70 °C
+ 25 °C
+ 0.5 °C
0 °C
– 0.5 °C
– 25 °C
– 40 °C
– 55 °C
Binary
MSB
LSB
00000000 11111010
00000000 10101010
00000000 10001100
00000000 00110010
00000000 00000001
00000000 00000000
11111111 11111111
11111111 11001110
11111111 10110000
11111111 10010010
Hex
00FAh
00AAh
008Ch
0032h
0001h
0000h
FFFFh
FFCEh
FFB0h
FF92h
Please note that the least significant temperature DATA-byte is in terms of a 0.5 ° C. The sign bit
is duplicated into all of the bits of the most significant DATA-byte.
The second format provided by this device for temperature is in IEEE Floating-Point Standard
(single precision) and has a useable resolution of 0.1 degree Celsius. Commands that query
register 2 in the Sensorsoft Thermometer will receive a four byte response in the DATA-byte(s)
placeholder. Decoding these IEEE Floating-Point bytes is beyond the scope of this document.
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Sensorsoft Thermometer User Manual
Reading the Sensorsoft ID Record
Every Sensorsoft device (SSD) accepts an identification (ID) command, whose response can be
used to uniquely identify the type of SSD currently connected. Specifically, the model number
and description can be extracted from the SSD’s ID response, allowing application software to
determine the specific model of the SSD connected and to configure itself appropriately.
The format of the ID command is identical to the format of all other commands, described earlier.
Send the following bytes to the SSD to request the ID:
<C3h><0Bh><00h><01h><00h><00h><00h><00h><00h><20h><5Eh>
The ID response contains four variable-length, null-terminated strings. The sequence of four
strings begins at the 10th byte in the response packet.
To read the SSD’s description, count to the 10th byte in the ID response and extract the following
ASCII null-terminated string.
Following this is the manufacturer’s name; also a null-terminated string.
The third null-terminated string is the SSD’s model number. The model number can be used to
uniquely identify the type of SSD, so that your software can configure itself appropriately for
different models of SSDs.
The fourth and final null-terminated string is the SSD’s firmware version.
Structure of the ID response packet
Byte
1
2-3
4-9
10
~
~
~
~
~
Description of field
Response byte
Packet length
Not used
Device name or description (null-terminated)
Manufacturer (null-terminated)
Model Number (null-terminated)
Firmware Version (null-terminated)
Record Terminator (FFh)
CRC bytes (2)
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Sensorsoft Thermometer User Manual
Sample ID response packet from a ST6105 Sensorsoft Thermometer
Byte
1
2
3
4-9
10
~
~
~
~
~
Contents
<90h>
<4Fh>
<00h>
<01h> <00h> <00h> <03h> <03h> <07h>
Sensorsoft (R) Thermometer<00h>
Sensorsoft Corp.<00h>
ST6105J<00h>
4.00<00h>
<FFh>
<CEh> <CBh>
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Sensorsoft Thermometer User Manual
Getting Help
Limited Warranty
Sensorsoft Corporation warranties Sensorsoft products to be free from manufacturing defects for
a period of two years. This includes parts and labor. All shipping and brokerage fees are your
responsibility when returning a Sensorsoft product for warranty claims. The following will void
the warranty and 30 day money back guarantee:



signs of water or chemical damage
cracks to the housing
signs of tampering or reverse engineering
Technical Support
If in the unlikely event you should have problems installing or using your Sensorsoft product and
the previous sections of this manual have failed to provide a solution, we offer technical support
to help you overcome your difficulties (see web site address below). No-charge installation and
configuration support is provided for 90 days, after that there is a per-incident fee. Sensorsoft
Corporation does not provide free support to those wishing to write their own software; this is
available on a charge-per-incident basis only. Please contact support for current rates.
World Wide Web:
E-mail:
http://www.sensorsoft.com
support@sensorsoft.com
30 Day Money Back Guarantee
If for any reason you want to return a Sensorsoft product for a refund, you can do so within 30
days (calendar days) of your purchase. The refund does not include shipping or brokerage fees
you may have incurred or paid.
Returns
If returning a product or item, please keep in mind the follow guidelines:



Contact Sensorsoft for an RMA number (Return Material Authorization).
Provide a detailed explanation or reason for returning the product.
Return shipments that bear no RMA number (on the outside of the package) or are not
prepaid for shipping/clearing charges, will be refused.
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Sensorsoft Thermometer User Manual
FCC Compliance and Advisory Statement
This equipment has been tested and found to comply with the limits for a Class A digital device
pursuant to Part 15 of FCC Rules. These limits are designed to provide reasonable protection
against such interference when operating in a commercial environment. This equipment
generates, uses, and can radiate radio frequency energy, and if not installed and used in
accordance with this guide, may cause harmful interference to radio communications. Operation
of this equipment in a residential area is likely to cause interference in which case the user, at his
or her own expense, will be required to take whatever measures may be required to correct the
interference.
Warning: Changes or modifications to this device not explicitly approved by Sensorsoft
Corporation will void the user's authority to operate this device.
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