RESI®
Title:
RESI-KNX-MBMASTER Manual
Date
Page
of
10.09.2018
28
30
.
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Now we make a very serious error in the reading procedure. We read both registers and build the hexadecimal
value in our host software in the wrong word order. First the lower word, then the upper word. The result is
also a 32 bit hexadecimal number: 0x41BB41BC instead of the correct number 0x41BC41BB. Now we convert
this hexadecimal number into an IEE754 floating-point number:
The result is 23.407097. That's not far from the original number 23.532095! Thus, this massive software bug
can live undetected for a long time. Only if the exchanged value generates physically meaningless values,
this error is recognized!
