Siemens 2D-TZ577 Instruction Manual page 16

3 Features and Specification of 2D-TZ577 Card
(5) Input/output data swapping
The 2D-TZ577 Card permits upper/lower bytes to be swapped at the time when input/output data is sent to
or received from Master Station. In a PROFIBUS DP network, the way the upper/lower bytes of input/output
data is treated differs depending on the type of Master Station, but there is no need for making input/output
data swapping at a program level.
(6) Global control
The 2D-TZ577 Card supports global control capability, enabling Class 1 Master Station to control
input/output data updating on the 2D-TZ577 Card by commands it transmits (SYNC, UNSYNC, FREEZE,
and UNFREEZE). For instructions on using the global control capability, see instruction manual which is
supplied with Class 1 Master Station being installed.
Features of 2D-TZ577 Card 3- 6