Siemens S7 appendix Options Tab, Option Meaning / Effect

Installing and Starting the Ethernet CP with STEP 7

Notice

Please note the following information on S7–300 stations:

If you selected the option ”Update OB1 process image cyclically” in the CPU confi- guration, (default), make sure that the start address of the CP is outside the pro- cess image area (start addresses in the ”Addresses” tab).

Example: if the process image selected for the CPU = 1024 (0...1023), an address >= 1024 must be selected for the CP.

Options Tab

Depending on the CP type, you can make the following settings:

Table 2-1 Settings in the “Options” Tab

Option	Meaning / Effect
S Time-of-Day Synchronization	Here, you decide whether the CP passes on time-of-day frames or
	not. You require this function if you have several CPs in a station
	since only one CP (on the same network) is permitted to pass on the
	time synchronization messages.

	Note
	The time-of-day synchronization function does not exist for all module
	types.
S Data transfer > 240 bytes	With this option, you specify whether or not the CP will support jobs
	with a data length of more than 240 bytes (for S7-300 stations).
	Notes
	S The transfer of more than 240 bytes of data is supported by
	newer version CPs. Please note the information in the product
	information bulletin / manual of the Ethernet CP.
	Please note the information in Section 5.1 on the
	newer CP types.
	S Remember that with this configuration on an S7-300, one
	connection resource (free connection for S7 functions) of the
	S7-300 CPU is used. CPU connection resources are also used,
	for example, by S7-300 CPs, in the FMS mode or by PGs and
	OPs. For more detailed information about the maximum
	connection resources, refer to /13/ and /7/.

SIMATIC NET NCM S7 for Industrial Ethernet	55
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