Axetris AG
LGD F200P2 Operating Instructions - Rev D
19.09.2018
38/60
should be resent from the start. If the flux is consistent with the timeout requirements, the 64 bytes are
read, checked for consistency and only considered if all conditions are fulfilled.
Very long commands > 64 bytes
For very long commands (> 64 bytes) it’s important that the packet transmission lasts a certain amount of
time. AXAG recommends adding a waiting time of 5 ms every 8 bytes during transmission, to lengthen the
transmission time and avoid problems. Every valid transmission to the sensor will be acknowledged.
3.6 Measurement data format
After connecting the power supply, the sensor sends a version packet (containing 64 bytes) and then
starts sending measurement packets continuously, roughly every second. All float and integer values have
the little endian format (according to Norm IEEE 754).
For different sensor types the measurement packets have the following format:
For CH
4
and CO
2
Applications (One measurement packet contains 16 Bytes.)
Bytes (Hex)
Description
Data Type
7B 4D
Begin of packet: open brace {M
2 Bytes
10 00
Packet size = 16
Unsigned Integer 16 Bit
00 00
Error code
2 Bytes
28 54 EE 45
Concentration gas 1
= 7626.52
1 Float
(single Precision)
00 00 00 00
zeros to reach packet size multiple of 8
4 Bytes
79
Checksum
1 Byte
7D
End of packet: close brace }
1 Byte
For NH
3
, HCl and other two gas Applications (One measurement packet contains 24 Bytes.)
Bytes (Hex)
Description
Data Type
7B 4D
Begin of packet: open brace {M
2 Bytes
18 00
Packet size = 24
Unsigned Integer 16 Bit
00 00
Error code
2 Bytes
05 71 47 42
Concentration gas 1
= 49.9 ppm
1 Float
(single Precision)
03 BC 4D 46
Concentration gas 2
= 13167 ppm abs. humid.
1 Float
(single Precision)
E0 AB F4 41
Temperature [°C]
= 30.6 °C
1 Float
(single Precision)
00 00 00 00
zeros to reach packet size multiple of 8
4 Bytes
0F
Checksum
1 Byte
7D
End of packet close brace }
1 Byte
Floats are coded based on IEEE754 - tools can be used under
http://www.binaryconvert.com/convert_float.html
to convert them.
(Bytes order should be reverted “Little endian.”)
Summary of Contents for LGD F200P2
Page 1: ...Operating Integration Instructions Laser Gas Detection OEM Module LGD F200P2 Axetris AG...
Page 57: ...Axetris AG LGD F200P2 Operating Instructions Rev D 19 09 2018 57 60 Notes...
Page 58: ...Axetris AG LGD F200P2 Operating Instructions Rev D 19 09 2018 58 60 Notes...
Page 59: ...Axetris AG LGD F200P2 Operating Instructions Rev D 19 09 2018 59 60 Notes...
Page 60: ...Axetris AG LGD F200P2 Operating Instructions Rev D 19 09 2018 60 60 Notes...
