Step7 - What are the individual SDBs in the System Database?

Does anybody know exactly what the individual SDBs in the System Database are and what their relationship to individual objects in HW-Config or NetPro is?

After getting the production line back up and running yesterday by loading the SDBs from a two year old backup (after modifying the data to reflect changes in the Beckhoff Profibus Terminals), I wasn't terribly surprised to discover that the Ethernet communication with the Statistics PC had died even though the NetPro data in the backup copy appeared correct (although with the same fault in the multi-project, that all the individual MPI and Profibus Networks had the same (default) address.

Anyway, I corrected the MPI and Profibus addresses and integrated the Ethernet Network then recompiled first in Netpro then in HW-Config without any errors (to get this far, I had to delete all the devices in HW-Config and Import a copy of the system configuration from the backup version of the program). Since I don't think it would go down too well with the customer if I shut the production line down for another ten hours today, I decided to do a block compare of the Online/Offline versions of the program, including the SDBs. The screen-dump shows the result.




I assume the last line simply reflects the work I had just done in NetPro, but what do the two SDB related messages mean (in everyday, practical terms!) and how serious are the consequences of downloading in this state likely to be?

Is there anywhere where I can find more info on the relevance of the SDBs? The help file barely mentions them in passing and doesn't even attempt to explain what they are for or where they come from - or if they do, I haven't been able to find it!

If anybody knows a bit more about the SDBs, I'd be very grateful if the y would share their knowledge.

Cheers

Roy

PS, I hope I'm not opening myself up to be one of the targets for Ron's rant, here!

Roy,

The only info I've seen is the 'generic list'...

- Double click on the 'System data' icon in the Block folder
- Press the 'Help' button
- Select the green hyperlink 'number of the system data block'


Not much help I know...

Kevin

Roy, one thing you can do to determine which SDBs are which is to start with a blank project and add hardware and connections one at a time. I'm pretty sure the 2000+ SDBs are related to ethernet modules and connections. I'm ot sure what value it would be to know what they are (you can't edit the SDB list) other than knowing which component is throwing up the error message when there is a problem.

Roy,

I found this under the help button in the system data block box.

The system data blocks (SDBs) are created by various applications, sometimes even by the CPU itself. The following table shows a list of SDBs and notes on how they are "created.“
SDB Number Created By...
0 Configuring Hardware
1 Configuring Hardware or by the CPU (after a complete restart)
2 CPU (standard parameter assignment after a complete restart)
3, 4, and 7 Configuring Hardware
5 CPU (MPI parameters)
22 to 89 Configuring Hardware (DP configuration)
90 to 99 Configuring Hardware (H and F systems)
100 to 149 Configuring Hardware (parameters for central and distributed configurations)
150 to 152 Configuring Hardware (parameters for interface modules)
153 to 189 Configuring Hardware (DP configuration)
200 Configuring Connections (S7-300)
210 Configuring Global Data Communication
3xx Configuring Symbol-Related Messages
7xx Configuring Connections
999 Configuring Networks/Connections (S7-Routing)
³ 1000 Configuring Hardware (DP configuration, parameters for CPs and FMs, S7-Routing, Connections)

Thanks a lot guys, especially JRW, that list is especially interesting since my fault message specifically mentioned SDB 200 and SDBs with number > 1000. After going back to the old backup I can now compile successfully, but I'm unable to get any Ethernet connections downloaded to the SPS. I can create my connections (actually they already existed in the backup), compile them successfully in NetPro and HW-Config and then download to the PLC, all without any error message. However if I now open up a new project and fetch the program back from the PLC the connections have disappeared.

It sounds like it might be worthwhile going back to the current (or rather last) program version and deleting and redoing everything to do with Ethernet.

That'll be a project for next week though!

Cheers

Roy

PS - just looked at the screen-dump again and with SDB 200 only present off-line, then perhaps it's no surprise that the Ethernet comms aren't working!

On another forum someone mentioned that downloading from the manager is not the same as downloading from NetPro when it comes to connections.
I asked what the difference is, but havent got the answer yet.
Anyway, it is a little bit surprising if it is correct, as I allways thought that the SDB folder in the manager was affected when you save and compile in NetPro. Maybe the above can explain why SDB200 is missing in the PLC.