Siemens SIMATIC NET Guide de l'utilisateur télécharger pdf (Page 15)

Configuring a Topic Definition 11

Select the name of the connection that will be used by this topic. Only connection

names that correspond to the selected CP and VFD are found in the list. Changing the

CP name and/or changing the VFD name changes the list contents of the connection

combo box. If you configure the S7 IO server offline (no S7 SAPI or board installed)

you can directly type in a connection name.

Enter the frequency (in milliseconds) that the server will acquire date for the

items/points associated with this topic. If set to zero, the server will not poll the PLC to

gather data.

Note Different items/points can be polled at different rates in a PLC by defining

multiple topic names for the same PLC and setting a different Update Interval in each

of the topics.

Select this option to disable the S7 SAPI cyclic services for items/points on this topic.

Cyclic services have a reliable update frequency and need less bus access. Cyclic

services are a limited resource in the PLC and/or Communication Processor. If this

option is selected, the server polls all items/points in this topic. If this option is not

selected, the server tries to register as many point/items in the cyclic services as

possible. The remaining points/items will be polled.

Some reasons for disabling cyclic services:

• A topic with a long interval should not occupy the cyclic service resource

• To force the server to attempt to collect data faster than 100ms

Note The mode 'cyclic' or 'poll' can be observed for each item in the monitor window.

See the section ‘S7 Data Monitor’ for further informations.

Enable this option to allow client modification of the update interval while the server is

in operation. If enabled, a client can read and write the update interval on this topic

using the item name UPDATEINTERVAL. If disabled, the client can only read the

Update Interval configured for the topic.

Note The actual update interval for the slowest item on this topic can be read using the

item name MAXINTERVAL. This gives you an indication of the performance of your

configuration during operation.

Selecting this option forces the server to read input and output blocks (also peripherals)

only if their address spaces are contiguous. Check this if you have some holes in your

PLC’s input or output address space.

1 2 ... 10 11 12 13 14 15 16 17 18 19 20 ... 67 68

Pas de commentaire

Siemens SIMATIC NET Guide de l'utilisateur Page 15