Coronis WaveTherm DALLAS, WaveTherm PT100, WaveTherm PT1000 User Handbook Manual
File : CS-SUP-MUTI-WTHERMAPP-E01.sxw
WaveTherm modules – application handbook page 1 of 65
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REVISIONS HISTORY
Rev. # Description Author Date Comments
1 Original document RCS 02/02/05 Version 1
2 Addon text FCC RCS 17/02/05 Version 2
SUPPORTED FIRMWARE VERSION
➢ WaveTherm - DALLAS
European Version
Manual version Firmware version Date
1.0 V 01.04 15/10/04
US Version
Manual version Firmware version Date
1.0 V 81.05 15/10/04
➢ WaveTherm - PT100
Manual version Firmware version Date
1.0 V 01.02 15/10/04
➢ WaveTherm - PT1000
Manual version Firmware version Date
1.0 V 01.00 15/10/04
This device complies with part 15 of the FCC rules. Operation is subject to the
following two conditions : this device may not cause harmful interference, and
this device must accept any interference received, including interference that
may cause undesired operation.
Caution : any changes or modifications not expressly approved by CoronisSystems could void the user's authority to operate the equipment.
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TABLE OF CONTENTS
1 PRESENTATION........................................................................................................................... 6
2 REFERENCE DOCUMENTS......................................................................................................... 6
3 PRESENTATION OF THE WAVETHERM MODULES FUNCTIONALITIES................................ 7
3.1 SENSORS INTERFACE.........................................................................................................................7
3.2 READ TEMPERATURES.......................................................................................................................8
3.3 PERIODIC TEMPERATURE READING (DATALOGGING)..................................................................8
3.4 MANAGEMENT OF THRESHOLD ALARMS........................................................................................9
3.4.1 Threshold Alarm Detection.............................................................................................................9
3.4.2 Storage of Threshold Alarm occurences........................................................................................9
3.4.3 Transmission of a Threshold Alarm Frame.....................................................................................9
3.5 STORAGE OF CALIBRATION PARAMETERS..................................................................................10
3.6 WAKE-UP SYSTEM MANAGEMENT..................................................................................................10
3.7 AUTOMATIC TRANSMISSION OF FAULTS......................................................................................10
3.8 SENSOR FAULT DETECTION (IF SUPPORTED BY THE MODULE)............................................... 11
3.9 END OF BATTERY LIFE DETECTION................................................................................................11
4 DATA EXCHANGE PRINCIPLE WITH A WAVETHERM MODULE .......................................... 12
5 INFORMATION RELATIVE TO THE PROBES ASSOCIATED WITH THE WAVETHERM
MODULES ...................................................................................................................................... 15
5.1 DALLAS PROBES...............................................................................................................................15
5.1.1 Coding of temperatures for the DALLAS probe type DS18B20 ...................................................15
5.1.2 Probe ID........................................................................................................................................15
5.1.3 Setting of the probe coefficient parameters..................................................................................16
5.2 PT100 AND PT1000 PROBES.............................................................................................................17
5.2.1 Representation of temperature values..........................................................................................17
5.2.2 Calibration of radio module...........................................................................................................18
5.2.3 Setting of probe coefficient parameters........................................................................................19
6 MODIFICATION OF THE INTERNAL PARAMETERS................................................................21
6.1 INTERNAL PARAMETERS LIST ACCESSIBLE BY RADIO COMMANDS....................................... 21
6.1.1 Parameters common to all WAVETHERM versions.....................................................................21
6.1.2 Parameters specific to the WaveTherm – DALLAS module.........................................................22
6.1.3 Parameters specific to the WaveTherm – PT100 module............................................................22
6.1.4 Parameters specific to theWaveTherm – PT1000 module...........................................................23
6.1.5 Definition of the module control bytes...........................................................................................24
6.2 PRINCIPLE OF READING AND WRITING OF INTERNAL PARAMETERS......................................25
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7 WAVETHERM MODULE FUNCTIONS ...................................................................................... 27
7.1 PARAMETER SETTING OF THE WAVETHERM MODULE...............................................................27
7.1.1 Reading of the module type..........................................................................................................27
7.1.2 Reading of the firmware version...................................................................................................28
7.1.3 Reading of the date and time of the module.................................................................................29
7.1.4 Setting the date and time of the module.......................................................................................30
7.1.5 Access to the user data area........................................................................................................31
7.1.6 Initialization of the sensors............................................................................................................33
7.2 READING THE CURRENT VALUE OF THE TEMPERATURE SENSORS........................................34
7.2.1 Information concerning precision..................................................................................................34
7.2.2 Description of the commands to be used.....................................................................................34
7.2.3 Reading the current ohmic values of the sensors.......................................................................36
7.3 WAKE-UP SYSTEM MANAGEMENT..................................................................................................37
7.3.1 Description of the parameters used..............................................................................................37
7.3.2 Choice of wake-up mode..............................................................................................................37
7.3.3 Set a new wake-up period............................................................................................................38
7.3.4 Set a fixed wake-up period for certain days of the week..............................................................38
7.3.5 Set day/night system parameter without distinction of days of the week.................................... 38
7.3.6 Set the day/night system parameters according to day of the week...........................................40
7.4 PARAMETER SETTING OF THE DATALOGGING MODE................................................................41
7.4.1 Description of the parameters used..............................................................................................41
7.4.2 Precision level of the measurement..............................................................................................41
7.4.3 Activating the datalogging mode...................................................................................................42
7.4.4 Index logging in time steps...........................................................................................................43
7.4.5 Index logging once a week...........................................................................................................44
7.4.6 Index logging once a month..........................................................................................................45
7.4.7 Reading the logged temperature values.......................................................................................46
7.5 ADVANCED DATALOGGING.............................................................................................................48
7.5.1 Description of the parameters used..............................................................................................48
7.5.2 Parameter setting of the Advanced Datalogging mode................................................................49
7.5.3 Principle of reading the temperature, and re-initializing the storage table....................................49
7.5.4 Reading the totality, or a part of the storage table........................................................................51
7.5.5 Structure of the data when two sensors are activated..................................................................54
7.5.6 Usage limit of the multi-frame mode.............................................................................................55
7.6 MANAGEMENT OF THRESHOLD ALARMS......................................................................................56
7.6.1 Description of the parameters used..............................................................................................56
7.6.2 Precision level of the measurement..............................................................................................57
7.6.3 Format of the temperature information.........................................................................................57
7.6.4 Principle of the detection modes...................................................................................................58
7.6.5 Selection of the threshold detection modes, and activation of the detection................................59
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7.6.6 Configuration of the measurement period of the threshold detection...........................................59
7.6.7 Reading the threshold detection table..........................................................................................60
7.7 MANAGEMENT OF THE ALARM FRAMES........................................................................................61
7.7.1 Description of the parameters used..............................................................................................61
7.7.2 Configuration of the route to reach the alarm frames recipient.................................................... 61
7.7.3 Configuration of the alarms to be sent..........................................................................................62
7.7.4 Triggering an alarm frame............................................................................................................63
7.8 END OF BATTERY LIFE DETECTION................................................................................................64
7.8.1 Description of the parameters used..............................................................................................64
APPENDIX A : SET OF THE APPLICATIVE COMMANDS.............................................................................65
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1 PRESENTATION
This document describes the functionalities of WaveTherm radio modules :
WaveTherm – DALLAS Used with DALLAS sensor
WaveTherm – PT100 Used with PT100 sensor
WaveTherm – PT1000 Used with PT1000 sensor
This document defines in an exhaustive way the applicatives data relating to serial dialog frames between a
Wavecard and a host equipment , used to reach the data of the WaveTherm radio module.
2 REFERENCE DOCUMENTS
Ref Title Reference Version Date
DR[1] WaveCard user handbook
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3 PRESENTATION OF THE WAVETHERM MODULES FUNCTIONALITIES
3.1 SENSORS INTERFACE
➢ WaveTherm – DALLAS :
The module is designed to manage to the maximum two DALLAS temperature sensors (type
DS18B20).
This DALLAS sensor of 1-wire type integrates a 12-bit internal converter.
Each external sensor is connected to the module by a cable equipped with a BINDER connector of
3-pin type.
An automatic identification of the temperature sensors allows to memorize the identifier of the
sensors. This phase is automatically carried out when powering the module
and is also activated on a specific radio request (in this case, The module returns by radio the
identifiers of the sensors).
➢ WaveTherm – PT100 :
The WaveTherm-PT100 module has the possibility to manage 1 or 2 PT100 temperature sensors.
The probes are connected to the module through impervious connectors allowing to connect 2, 3 or 4
wires probes.
➢ WaveTherm – PT1000 :
The WaveTherm-PT1000 module has the possibility to manage 1 or 2 PT1000 temperature sensors.
The probes are connected to the module through impervious connectors allowing to connect 2, 3 or 4
wires probes.
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3.2 READ TEMPERATURES
The WaveTherm module has the following possibilities:
To read the current temperature ;
To transmit the last N temperatures stored, in one frame.
If two temperature sensors are used, then the WaveTherm return the last N/2 values of each sensor.
• WaveTherm – DALLAS : N = 48 temperatures
• WaveTherm – PT100 : N = 24 temperatures
• WaveTherm – PT1000 : N = 24 temperatures
3.3 PERIODIC TEMPERATURE READING (DATALOGGING)
Periodic reading of temperatures is available in two versions. In both cases, the module may be configured to
store the temperatures measured periodically (in time intervals ranging from a minute to several hours), once
a week or once a month.
➢ Standard datalogging :
Periodic collection of temperature measurements up to N temperatures. In this case, it functions in
'permanent loop' mode, i.e. the most recent measurements replace the oldest measurements.
WaveTherm – DALLAS : N = 48 temperatures;
WaveTherm – PT100 : N = 24 temperatures;
WaveTherm – PT1000 : N = 24 temperatures.
➢ Advanced datalogging:
Periodic collection of temperature measurements up to M temperatures. In this case, it functions in
'stop memory full' mode.
WaveTherm – DALLAS : M = 4500 temperatures;
WaveTherm – PT100 : M = 2000 temperatures;
WaveTherm – PT1000 : M = 2000 temperatures.
Remark : Only the 'Stop memory full' mode is currently operational : when the memory corresponding to N
temperatures is full, datalogging stops automatically.
A new parameter setting cycle must then be started with a specific radio command.
A future upgrade will enable permanent looping with indication of looping.
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3.4 MANAGEMENT OF THRESHOLD ALARMS
The WaveTherm module detects when the values exceed the threshold levels (high or low) for a given period
of time.
The WaveTherm – PT100 and PT1000 may be configured with a precision level offering a more reliable
measurement even in environments with excessive interference (see chapter 7.2.1).
Three types of threshold alarm detection methods may be programmed :
immediate threshold alarm detection
threshold alarm detection for a given continuous period of time (successive mode)
threshold alarm detection for a total period of time (cumulative mode)
3.4.1 Threshold Alarm Detection
Threshold alarm detection requires periodic measurement of the temperature for a predefined period. The
value of this period enables establishment of the threshold alarm detection reactivity.
This period is set independent of the datalogging period. However, for power saving reasons, it is
recommendable to set the datalogging period as a multiple of the threshold alarm detection period.
The following parameters apply to this function:
High threshold alarm,
Low threshold alarm,
Threshold excess time (used in cumulative and successive mode),
Mode parameter setting byte (high threshold enabled, low threshold enabled, immediate,
successive or cumulative mode).
3.4.2 Storage of Threshold Alarm occurences
Threshold alarms are stored in a memory zone which may be accessed by radio. If the number of threshold
alarms exceeds the memory storage capacity, the oldest alarms recorded are deleted.
The following information is recorded in the table:
Threshold alarm detection date
Threshold alarm detection duration
The average value of all measurements recorded during the alarm period.
3.4.3 Transmission of a Threshold Alarm Frame
The module may be programmed to transmit a radio frame as soon as a threshold alarm is detected.
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3.5 STORAGE OF CALIBRATION PARAMETERS
The WaveTherm module manage a non-volatile memory area accessible by radio command, and allowing to
store up to 32 bytes.
This area is not used by the internal process, and is generally used to store the parameters relative to the
calibration of the module, and can be read, or modified by specifying the start address, and the size of the
data.
3.6 WAKE-UP SYSTEM MANAGEMENT
In order to reduce module power consumption, a wake-up period parameter setting system is incorporated.
This system enables modification of the module wake-up period (default setting 1 s) by entering a time and
day of the week :
The wake-up period default value may be modified;
Two time-windows with different wake-up periods may be defined;
Each day of the week may be set in one of the following three cases :
• Wake-up period default setting
• Wake-up according to predefined time windows
• No wake-up period (for safety reasons, the module is not disabled on reception and it
wakes up every 10 seconds)
Note : The system is disabled by default and must be enabled by writing a specific profile in the
wake-up system status word.
3.7 AUTOMATIC TRANSMISSION OF FAULTS
The WaveTherm module offers the possibility to automatically transmit radio frames when an occurrence is
detected.
The following occurrences may provoke an automatic alarm:
Threshold detection (see chapter 7.6)
End of battery life detection (see chapter 7.8)
Probe fault detection (WaveTherm – PT100 and PT1000 only)
It is possible to select for each type of occurrence whether or not an alarm frame is to be sent.
The radio address of the receiver module and the repeater path must be preset with a radio signal.
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3.8 SENSOR FAULT DETECTION (if supported by the module)
For all modules, temperature probe absence or error detection is carried out during a write request and is
indicated by the presence of a specific value which does not correspond to a possible temperature value.
However, in the case of the WaveTherm – PT100 and WaveTherm – PT1000 modules only, after
detection of a probe fault, the module carries out the following operations:
records the detection date in internal parameters (0x91 ; 0x92).
If required, transmits an immediate probe fault detection radio frame.
3.9 END OF BATTERY LIFE DETECTION
To detect the end of battery life, the WaveTherm module uses the power metering principle rather than
measurement of the battery voltage. Lithium batteries are, in particular during passivation, unsuitable for the
voltage measurement method to determine the remaining capacity.
The WaveTherm records and evaluates all events (measurements, transmissions) to decrement the power
meter according to the battery used. When the meter passes below a predefined threshold, the “end of
battery life” is signalled with the Application Status byte.
The initial value of the end-of-life meter is factory-set. It depends on the type and number of batteries used.
When the end of battery life is detected, the detection date is memorised and may be read with a radio
command.
Please refer to the WaveTherm module technical specifications, for more details on the life of the modules.
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4 DATA EXCHANGE PRINCIPLE WITH A WAVETHERM MODULE
The WaveTherm module uses the WAVENIS protocol.
The choice of mode used is initiated by the read element which uses a different set of commands (see
WaveCard document) when sending commands to the WaveCard.
The following chart indicates the read modes possible as well as their typical applications.
Read mode Description Recommendations
Peer-to-peer Individual reading with re-transmission management
in case of no reply
Standard use
Polling This mode enables successive polling of several
modules in a single operation .
The principle consists of waking up several modules
with the 1st radio transmission.
To be used when module reading time is
an important factor.
Re-transmission not possible.
Broadcast and multicast (*) This mode enables use of a single frame to address
all radio modules within reception range.
The multicast mode may only address one group of
modules.
This mode enables reading of modules
without knowing their radio address.
Type of use: detection of radio modules
within range of the emitter module
(installation phases).
➢ Additional functions:
Additional
functions
Compatibility Description Recommendations
Repeater Only used in point-
to-point mode.
This function enables use of a radio module to relay
a frame which was not initially intended for this
module.
This is a default function of the WaveTherm module,
i.e. it may be read via several repeaters but may
also act as a repeater itself when reading another
unit.
This function is used when the caller
module and the target WaveTherm
module are outside radio range.
The maximum number of repeaters is
limited to 3.
Attention: collection of data in multi-frame mode (advanced datalogging) is not possible in
repeater mode.
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➢ Example in Point-to-point mode :
Remark : Generally, the exchanges examples given in this document will be in Point-to-point mode,
except when the context depends directly on the mode of exchanges.
This type of radio exchange allows to send a request, then to await a response of the remote equipment.
Note : the commands of Point-to-point exchanges, have the following format: (all the exchanges
modes are treated in document [DR1])
CMD NAME DESCRIPTION
0x20 REQ_SEND_FRAME
Request to send a radio frame with the waiting for the radio response.
0x30 RECEIVED_FRAME
Received radio frame by the radio board.
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The data field of each command must be formatted according to the following table :
CMD
DATA
6 bytes variable ( max : 152 bytes)
0x20
Radio address from equipment to reach
Data to transmit
0x30
Radio address from transmitter
equipment
Received Data
the first byte of the field 'data to transmit' (or 'Received Data') contains an applicative command (or its
acknowledgement). That allows to the receptor of the frame to identify the type of requests (or of responses).
Data to Transmit or Received Data
1 byte 151 bytes
REQ_SEND_FRAME Applicative command Data relating to the request
RECEIVED_FRAME
Acknowledgement of the
applicative command
Data relating to the response
The commands set is available in Appendix A.
ATTENTION, This document describes only the format of the fields 'Data to Transmit', 'Received Data'.
These fields are directly dependent on the access to the functionalities of the WaveTherm modules. The
other fields of the radio frame depend on the exchanges modes chosen, and are detailed in document
[DR1].
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5 INFORMATION RELATIVE TO THE PROBES ASSOCIATED WITH THE
WAVETHERM MODULES
5.1 DALLAS Probes
5.1.1 Coding of temperatures for the DALLAS probe type DS18B20
These probes have a resolution of 12 bits and their value is coded on two bytes (MSB first)
Negative values are expressed in two's complements with addition of a sign.
MSB LSB MSB LSB
Most Significant Byte Leasr Significant Byte
b7 b6 b5 b4 b3 b2 b1 b0 b7 b6 b5 b4 b3 b2 b1 b0
S S S S 2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
2
-1
2
-2
2
-3
2
-4
Unit : Celsius degree (°C)
Bits [b7:b3] : sign bit.
Remark: The hexadecimal value 0x4FFF indicates the absence of a probe, or a connection error between
the module and the probe.
Some temperature values:
Temperature Binary value (MSB First) Hexadecimal value
+125°C 0000 0111 1101 0000 0x07D0
+85°C 0000 0101 0101 0000 0x0550
+25°C 0000 0001 1001 0000 0x0190
0°C 0000 0000 0000 0000 0x0000
-10.125°C 1111 1111 0101 1110 0xFF5E
-55°C 1111 1100 1001 0000 0xFC90
5.1.2 Probe ID
The probe ID corresponds to a unique code attributed to each DALLAS temperature probe in the factory.
This code is composed of 8 bytes defined as follows:
MSByte LSByte
1 byte 6 bytes 1 byte
Family Code Serial n° (48 bits) CRC Code
The family code is used to distinguish between the probes used:
Probe DS18S20 : 0x10
Probe DS18B20 : 0x28
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5.1.3 Setting of the probe coefficient parameters
The precision of DALLAS probes is indicated by the manufacturer as ±0.5°C (-10°C to +85°C) and requires
no calibration before use.
However, it is possible to improve this precision if the user wishes to calibrate the probe. In this case, the
WaveTherm module contains a 32-byte memory zone for storage of transfer coefficients after calibration.
Initially, two parameters was created (size: 2 bytes per parameter), each one being able to store the value of
a coefficient of transfer.
After calibration, this allowed to refine measurement with a 2 degrees polynomial to the maximum.
Thereafter, a more important memory area was implemented, in order to store user data. Users can use this
area for whatever they want, but in order to increase the measurement precision, this 32-bytes area allows to
store a more significant number of coefficients.
Consequently the polynomial used can be superior degrees to 2; and allows to obtain a finer sleeking of
information. Management of this memory area is described further in chapter 7.1.5.
Remark : To maintain compatibility with old versions of the modules (Is)Thermeter), the storage
parameters of the coefficients are always existing, and are accessible by commands of reading and
writing of internal parameters.
Parameter 0x25 : parameter A relating to sensor 1
Parameter 0x26 : parameter B relating to sensor 1
Parameter 0x27 : parameter A relating to sensor 2
Parameter 0x28 : parameter B relating to sensor 2
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5.2 PT100 and PT1000 probes
5.2.1 Representation of temperature values
Due to the high level of precision required of the temperature values processed by the module,
WaveTherm PT100 or PT1000 are true numbers (with a mantissa and exponent).
They are represented in the form of a 32-bit floating number.
The format used is the standard IEEE format with precision coded on 32 bits (+/-5.8774e-39 to
+/- 170,14e36)
➢ Theoretic representation of a floating IEEE 32-bit in bytes :
➢ Representation of the floating numbers in the radio buffer:
The radio module represents the 32-bit floating data in its buffers by coding them in LSB first. This is the
standard representation format used by the compilers C/C++ on PC.
A shift of the exponent allow to code it from E-127 to E+128
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5.2.2 Calibration of radio module
➢ Factory calibration
The precision of PT100 and PT1000 probes is such that the WaveTherm module measurement chain
requires calibration.
This calibration is carried out automatically in the factory and the product is supplied ready for use.
➢ Re-calibration on site
Re-calibration on site is possible under certain conditions.
To carry out this operation, it will be necessary to connect two calibration precision resistances.
Remark: Calibration is therefore only possible on WaveTherm PT100 (or PT1000) modules equipped with
two probe inputs.
The WaveTherm PT100 and PT1000 modules possess two module calibration parameters. These
parameters are accessible in read-only and are updated with a calibration command
They contain the internal reference resistance values used during temperature measurement.
Parameter 0x30 : value of the internal reference resistance very low
Parameter 0x31 : value of the internal reference resistance very high
Calibration is therefore carried out using precision calibration resistances for accurate measurement of the
internal reference resistances and storage of the associated results in internal parameters. These values are
then used during temperature measurement.
Remark : Calibration resistance value:
- for WaveTherm – PT100 : 60 and 160 ohms.
- for WaveTherm – PT1000 : 160 and 1600 ohms.
➢ Associated radio commands
Applicative Command Description
0x08 Request to calibrate the radio module
0x88 Response to the request to calibrate the radio module
contents of REQ_SEND_FRAME request
Data Field (max : 152 bytes)
Applicative
Command
Value of the internal
reference resistance very low
(float - LSB First)
Value of the internal reference
resistance very high
(float - LSB First)
1 byte 4 bytes 4 bytes
0x08
The fields concerning the values of the internal reference resistors must be indicated with 32-bits
floating numbers ( LSbyte first). A more precise description of the 32-bits floating number format is
indicated in chapter 5.2.
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contents of RECEIVED_FRAME response
Data Field (max : 152 bytes)
Acknowledgement
of the applicative
command
Status de l'étalonnage
Reference resistance
A
(LSB First)
Reference resistance
B
(LSB First)
1 byte 1 byte 4 bytes 4 bytes
0x88
0x00 : calibration OK
0xFF : calibration error
Resistances A and B are restored in the 32-bits floating numbers format (LSB first). Format described in
chapter 5.2.
5.2.3 Setting of probe coefficient parameters
The PT100 and PT1000 probes have a coefficient providing a linear temperature response.
Remark : The European standard EN60751 relative to probes defines 3 coefficients A,B and C used in
the calculation of the relationship : resistance = f (temperature).
In the -200 to 0°C range : R = R0[1+At + Bt
2
+ C(t – 100°C)t3)
in the -0°C to 850°C range: R = R0(1+At + Bt
2
)
R0 : Resistance at 0°C
A, B and C: transfer coefficients
As the WaveTherm module operating mode consists of measuring the probe resistance and then calculating
the temperature, it requires coefficients in order to calculate the relationship between these values:
temperature = f (resistance)
and not resistance = f (temperature).
The relationship T = f(R) must therefore be calculated according to the relationship provided in standard
EN60751.
The following polynomial is used:
T = C7.R7 + C6.R6 + C5.R5 + C4.R4 + C3.R3 + C2.R2 + C1.R + C
0
where C7, C6, C5, C4, C3, C2, C1, and C0 are the parameters to be transferred to the radio module
The coefficients to be transferred to the radio module are based on the coefficients A,B and C (given by the
manufacturer of the PT100 or PT1000 probes) in a mathematical formula. When required, CORONIS is able
to provide a utility enabling calculation of these coefficients. There are 8 in total (coeff A to H).
They are managed with standard internal parameters read and write commands. (see chapter 6.2).
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All coefficients are regarded by the radio module as a single parameter.
Parameters Description
0x32 Coefficients of probe 1
0x33 Coefficients of probe 2
Each parameter is composed of 8 coefficients of 32 bits (floating IEEE) with a total size of 32 bytes.
The coefficients are represented in the radio buffer during use of the parameter read/write commands as
follows :
Remark: Coeff A : C
0
Coeff E : C
4
Coeff B : C
1
Coeff F : C
5
Coeff C : C
2
Coeff G : C
6
Coeff D : C
3
Coeff H : C
7
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