Generating The Checksum - Bosch Rexroth OptiFeed-FS EcoDrive 03 FLP04VRS Functional Description

10-20
Interface

Generating the Checksum

Examples: 1. #_N0000_POI _ 1_ _ _ _ +123456,789_123_ $
2. #5N0123_NOP _ _$
Character Hex
# 23
_ 20
N 4E
0 30
0 30
0 30
0 30
_ 20
P 50
O 4F
I 49
_ 20
1 31
_ 20
_ 20
_ 20
_ 20
+ 2B
1 31
2 32
3 33
4 34
5 35
6 36
. 2E
7 37
8 38
9 39
_ 20
1 31
2 32
3 33
_ 20
Fig. 10-16: Generating the Checksum
•
The sum of all 'ASCII' characters is calculated, from the first control
character to the last character before the '$.'
•
Then, the 'High Byte' is added to the 'Low Byte.' A transmission
occurring during this time is ignored.
•
The Two's Complement of the 'Low Byte' of this sum results in the
checksum
Example 1: #_N0000_ 1_ _ _ _ +123456,789_123_ $C4
Sum: 636 Í 06 + 36 = 3C. The Two's Complement of 3C is C4.
Example 2: #5N0123_NOP _ _$45
Sum: 2B9 Í 02 + B9 = BB. The Two's Complement of BB is 45.
ECODRIVE03-FL*-04VRS
∑ Hex
Character
23 #
43 5
91 N
C1 0
F1 1
121 2
151 3
171 _
1C1 N
210 O
259 P
279 _
2AA _
2CA
2EA
30A
32A
355
386
3B8
3EB
41F
454
48A
4B8
4EF
527
560
580
5B1
5E3
616
636
DOK-ECODR3-FL*-04VRS**-FK01-EN-P
∑ Hex
Hex
23 23
35 58
4E A6
30 D6
31 107
32 139
33 16C
20 18C
4E 1DA
4F 229
50 279
20 299
20 2B9