Table 1 lists all the possible values when measuring temperature
Alarm code
Meaning
A00
No alarm, the temperature value is within the limits
A03
no sensor element detected
Table 2 lists all the possible values when measuring humidity
Alarm code
Meaning
A00
no alarm, the humidity value is within the limits
A03
no sensor element detected
The sum is calculated according to the following algorithm with reference to example 1:
1.
Add up the decimal representation of all ASCII characters from “@“ to the final „;“
64 („@“) + 84 („T“) + 59 („;“) + 43 („+“) + 48 („0“) + 50 („2“) + … + 54 („6“)+ 55 („7“)+ 56 („8“) + 59 („;“) = 1991
2.
Divide this sum by 256 to find the remainder
1991 % 256 = 199
3.
Subtract the remainder from 255
255 – 199 = 56
4.
Interpret the decimal result as a hexadecimal number
56 = 38
hex
5.
Compare the individual hexadecimal numbers with the transmitted ASCII characters of the checksum
38
hex
→
„3“ & „8“
√
VisualPMU Freeware for RS232
This simple and very clear visualisation software supports the data output of a sensor via a serial interface on the PC or
laptop without an additional power supply.
To use this, it is necessary to install the accessory
Sub-D data line
(refer to accessories and connection diagrams). For USB
connections, a
USB adapter
can be supplied (see accessories).
The relative humidity, the dew point and the temperature (°C or °F) can be displayed and can be depicted as a graph.
Apart from that, the programme has a simple data logger function. Recorded data can be exported to other programmes.
This freeware version can be found on our Homepage as a free download (http://melasensor.de/download/).