
LRF 7047- Integrator Manual
914929_TML_LRF7047_en_Version B
Public: 04.2019
Confidential & Proprietary
Safran Vectronix AG – All rights reserved
Page: 40/72
Checksum
:
The checksum is the total sum in hexadecimal value of the message string between the
‘>’ and the ‘*
Characters
ASCII value in
Hex
Sum in Hex
L
4C
4C
M
4D
4C+4D = 99
,
2C
99 + 2C = C5
.
.
.
.
.
.
.
.
.
0
30
... = 71C
1
31
71C + 31 = 74D
Checksum
4D
Table 1: Example of checksum calculation
The checksum represents the 8 least significant bits of 74Dh (last row in column “Sum in Hex” of
Table 1.)
EOM
(End Of Message):
<CR> (ASCII 0x0D) indicates the end of the message frame. In the different examples,
carriage
return is written as <0D>.
Minimum message length (host to LRF module): 10
Maximum message length (host to LRF module): 16
Acknowledge
:
Acknowledge is sent by the LRF module to indicate that the message is valid and being
processed. Acknowledge is sent with checksum: >AC*<CS><CR> (">AC*84\r")
Not
Acknowledge
:
Not Acknowledge is sent by the LRF module to indicate that the message has been received, but is
not valid and has not been processed. The Not Acknowledge answer frame has an error ID as
parameter and a checksum. The Error ID parameter is an integer described in the Table 2.
Error
Description
0
Message checksum error
1
Message is not supported / implemented
2
Invalid parameter(s)
3
Serial interface Rx Parity bit error
4
Serial interface Rx overflow error
5
others
Table 2: Not acknowledge error list
Example for an invalid parameter error:
>LM,Md,3,0*31
<0D>
>NA,2*ED
<0D>
!
Example for a checksum error:
>LM,Md,3*D6
<0D>
>NA,0*EB
<0D>
!