Operating Instructions
LMS1xx Laser Measurement Sensors
Product description
8012471/ZN27/2017-06-09
© SICK AG · Germany · All rights reserved · Subject to change without notice
49
Chapter
3
3.12
Data communication using telegrams
The LMS1xx sends telegrams over the interfaces described above to communicate with a
connected host. The following functions can be run using telegrams:
request for measured values by the host and subsequent output of the measured
values by the LMS1xx
parameter setting by the host for the configuration of the LMS1xx
parameters and status log querying by the host
The telegrams each comprise a frame (see
section 3.12.1 “Frame and coding for the
) and the data.
You will find a detailed description of the different telegrams in the document “Telegram
Listing Laser Measurement Sensor”, part no.: 8014631, issue in English.
Please see
section 1.5 “Further information” on page 9
3.12.1
Frame and coding for the telegrams
The data frame varies depending on the coding.
Telegrams with ASCII coding
The frame for the serial host interface can be configured in SOPAS ET: P
ROJECT
TREE
, LMS…,
I
NTERFACES
, S
ERIAL
, area S
ERIAL
HOST
INTERFACE
.
In this way, for example, you can use two stop bytes (e.g. to end telegrams with CR/LF).
Telegrams with binary coding
Calculation of the checksum
The checksum is calculated using an XOR operator for every byte of the data, that is without
the frame.
Frame
Telegram
Frame
Code
STX
Data
ETX
Length (byte)
1
30 kB
1
Description
Start of text character
ASCII coded. The length is dependent on the previous
send telegram.
End of text character
Tab. 12:
Frame for the telegrams with ASCII coding
Frame
Telegram
Frame
Code
STX
STX
STX
STX
Telegram length
Data
Checksum
Length (byte)
1
1
1
1
4
2,495
1
Description
Start of text character
Length of the data
without CS
Binary encoded. The length is
dependent on the previous
send telegram.
See
further below
Tab. 13:
Frame for the telegrams with binary coding