SMC Networks EX245-EA2 Series - Page 64

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No.EX※※-OMW0011-B
・ I/O byte swap function
The data construction of each parameter of the byte swap function is as follows based on the
connected device process data size and the mapping size of the master communication
process data.
When the process data size of the connected device and mapping size of the master
communication process data are identical
(E.g.: connected device process data size: 8-byte, mapping size: 8-byte)
Table. 9-11 I/O byte swap function example for 8-byte
Parameter
Data construction
Direct (No swap)
0x0123 4567 89AB CDEF
Swap 16 bit
0x2301 6745 AB89 EFCD
Swap 32 bit 0x6745 2301 EFCD AB89
Swap All
0xEFCD AB89 6745 2301
∗: When the mapping size is 2-byte, even though the swap is set to 32bit, the byte will not be
swapped.
When the process data size of the connected device and mapping size of the master
communication process data are different
(E.g.: connected device process data size: 10-byte, mapping size: 16-byte)
Table. 9-12 I/O byte swap function example for 10-byte
Parameter
Data construction
Direct (No swap)
0x0123 4567 89AB CDEF GHIJ 0000 0000 0000
Swap 16 bit 0x2301 6745 AB89 EFCD IJGH 0000 0000 0000
Swap 32 bit
0x6745 2301 EFCD AB89 0000 IJGH 0000 0000
Swap All
0x0000 0000 0000 IJGH EFCD AB89 6745 2301
∗: When the mapping size is 2-byte, even though the swap is set to 32bit, the byte will not be
swapped.
∗: When the mapping size of the master connection process data and the process data size of
the connected device are different, swap the byte including the blank byte zero.