File : CS-SUP-MUTI-WTHERMAPP-E01.sxw
7.4.7 Reading the logged temperature values
Standard datalogging allows a periodic collection of temperature measurements up to N temperatures. If two
temperature sensors are used, then the WaveTherm return the last N/2 values of each sensor.
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.
The reading of N logged temperatures is accomplished by sending the following commands :
Applicative Command Description
0x03
Request to read the datalogging storage table
0x83
Response to the request to read the datalogging storage table
The format is as follow :
Contents of the request REQ_SEND_FRAME
Data Field (max : 152 bytes)
Applicative Command
1 byte
0x03
Contents of the response RECEIVED_FRAME
Data Field (max : 152 bytes)
Acknowledgement
of the applicative
command
Operating
Mode
Application
Status
Sensor A
storage
table
Sensor B
storage
table
Date of the
last logged
temperature
Measurement
period
1 byte
1 byte
1 byte
48 bytes
48 bytes
6 bytes
1 byte
0x83
(3)
(3)
(2)
(1)
(1) Measurement period :
the format of this byte is given in chapter 7.4.4.
ATTENTION : The 'Measurement Period' field is updated only when datalogging in time steps is
enabled. In the other modes, this field is not significant.
(2) Date of the last logged temperature :
the format of this field is equivalent to the standard date and time
format (see chapter 7.1.3).
(3) Temperature storage table :
the format is different according to the module used, see next page.
WaveTherm modules – application handbook
page 46 of 65
