Lantronix CoBox-FL, User Manual

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UDP
To get and set the node configuration, 120 bytes should be exchanged at once in 32-Byte
A
k e
r th t in t e li . S ce e ch cks m is a two-digit
h rese v lue from to 55.
T by summin h val e d ta o the line and taking the two’s
c the sum.
N ng lon r t ch s
E
R ta
A b tored at 0030, 0031, and 0032)
.2.5 Calculating the Two’s Complement
d to the number to reach a
Hexadecimal value of 100 (256 in decimal). In the example above, E2 + 1E = 100.
You can also calculate the two’s complement by subtracting the sum from 100. Using the
example above again, 100 - E2 = 1E. It may help to use a scientific calculator.
records. The IP address in the record (bytes 0 to 3) will be ignored (unless the UDP FD
command is being used).
8.2.4 Calculating the Checksum
s mentioned in
Table 20 - Bloc Typ s
above, the last two characters of an Intel Hex setup
ecord represent a checksum of
lue, it can rep
e da a h ne in th e u
exadecimal va nt a a 0 2
he checksum is calculated
omplement of
g t e ue of th a n
ote: Do not include the leadi co o he eck um byte in the sum.
xample:
0300300002337A1E
ecord length: 03 (3 bytes of da )
ddress: 0030 (the 3 bytes will
ecord Type: 00 (normal da a)
e s
R t
Data: 02, 33, 7A
Checksum: 1E
03 + 00 + 30 + 00+ 02 + 33 + 7A = E2
The two’s complement of E2 is 1E. See
Calculating the Two’s Complement
below.
8
The two’s complement of a number is the value that must be adde
8-6 CoBox-FL User Guide