50
ICC
Figure 22: BACnet - Modbus (Binary Objects & Discretes) Little Endian
However, when the database is configured for a big-endian byte order, binary
values 1…8 correspond to coils 9…16, binary values 9…16 correspond to coils
1…8, and so on. This can be seen in Figure 23. Since the most significant bytes
of the Modbus registers that the coils map to are now mapped to lower
addresses, the alignment between the two networks’ bit-wise data is byte
swapped. While this alignment can still be used, it is much more intuitive when
the database is configured to be little endian.
Figure 23: BACnet - Modbus (Binary Objects & Discretes) Big Endian
