In order to reduce the time investment needed for project creation and finalization, ETS5 reintroduces the possibility of performing parallel downloads. Parallel download is only allowed under the following conditions:
- Parallel in different topology lines
- Parallel means simultaneous download, but in different lines (i.e. to the devices). This does not mean that several devices in one line are downloaded in parallel (as was the case in ETS3.0d, but which sometimes caused problems with older generation devices because of higher bus line traffic).
- Only for IP connections (IP tunneling/IP interface connection); To prevent topology violations (IP couplers are, by definition, each linked to another, unique TP line).
Consequently, for every line, an individual "download connection" must be defined. These settings can be made in the line properties.
How Does It Work?
- On starting a download, ETS checks for the existence of possible line "download connections" in the topology.
- For each line which has an individual connection, ETS creates an internal queue, and so, each queue represents a line. For every line that has no individual connection, the standard or project connection will be used (see priority rules in the communication Settings).
- The devices to be downloaded are subsequently put into the respective queue (this does not necessarily mean all devices in a line --> multiple selection or filter result).
What is Parallel?
Only online operations which directly address a device even come into question for parallel downloading. This means that parallel applies only to device-related online operations of the types Download, Unload or Device Info. Other online operations such as Set Individual Address are defined as a broadcast (addressed to all) or a network operation and therefore do not fall into this category.
They are routed via the ETS interfaces according to their priority.
Limitations
Plug-ins
For a download, ETS always creates a data set of the current device configuration which is then downloaded to the device. Parallel downloading presupposes simultaneous ETS access of several devices in the project (multi-instance capability). For devices with plug-in software, this is not necessarily always a given because there are certain types here which only provide ETS with the data set upon request.
This creates an access problem when the same device is used several times in the project, but the plug-in can only be invoked simultaneously once. Consequently, these devices cannot be downloaded in parallel and ETS will issue a notification in such a case.
When such a case occurs, ETS then organizes all parallel activities in a sequential order (it still works, but it is slower because they are no longer parallel).
Line connection
A connection once placed on a line remains completely unchanged even when this connection is unavailable or is deleted in the settings. An update would not make sense because the project can also be exported and then imported to another computer (the interface connections could then already be present on this computer).
In the event of non-availability (see above), the Priority Rules apply for the use of interfaces. The download itself is thereby always safeguarded in the end.
The Device Info function also allows "parallel" reading. It is possible to read out several devices simultaneously. The same restrictions apply for this as for plug-ins as described above.