Page 70 - Basic Course

KNX BASIC COURSE

Data formats
Different data formats are necessary for processing data. The contents of the data formats
can be presented in binary, decimal or hexadecimal form.

Number conversions
In order to be able to switch between the different numbering systems, values must be
converted.

Converting a binary or hexadecimal number into a decimal number
The number is split up into its individual powers, which are then added up.
0
1
2
e.g.: 0A9HEX = 0 x 16 + 10 x 16 + 9 x 16
= 0 x 16 x 16 + 10 x 16 + 9 x 1
= 169DEC

Converting a decimal number into a binary or hexadecimal number
The number is constantly divided by the base of the target numbering system (binary or
hexadecimal) until the original number equals zero. The remainder of each division form
the digits of the converted number, when read from back to front.
e.g.: Division Remainder
169 : 2 = 84 1
84 : 2 = 42 0
42 : 2 = 21 0
21 : 2 = 10 1 Reading order
10 : 2 = 5 0
5 : 2 = 2 1
2 : 2 = 1 0
1 : 2 = 0 1
169DEC = 1010 1001BIN

Converting binary numbers into hexadecimal numbers
Often binary numbers can be converted more quickly if they are split into tetrads. Each
tetrad then corresponds to a number in the hexadecimal system. Leading zeros may be
added.
e.g.: 0000 1010 1001 BIN
0 A 9 HEX

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