Sorry, meant DH+ where I typed DF-1.
Here's the basic situation. Consider a plant that has a lot of different types of PLCs (SLC 5/04's and different models of PLC 5's mostly). If you start connecting all of these together with DH+ links you end up saturating the links since they are only 57K and the inter-PLC communication gets very much bogged down. Bumping up the communication to 230K helps a little, but not much, and a lot of equipment doesn't run very smoothly at 230K so that's not really a solution. One thing you can do is buy a bunch of Control Logix chassis and populate them with DH+ cards and ethernet cards. This allows you to segment up your DH+ networks and bridge them together with ethernet links. This works fairly well, once you go through the royal hassle of figuring out how to set up the routing tables in the Control Logix gateway and figure out how to do the message routing on the PLCs.
However, you still have a problem, in that each local DH+ link is fairly low bandwidth. One solution to this is to start using ControlNet links in place of the DH+ links. Since ControlNet is much more configurable, you can bump up the data rate considerably and get rid of some of the bottlenecks in the system.
You can also start using ethernet capable PLCs like the PLC 5/80E.
So now to the root of the problem (my problem). We make a device which sits on the DH+ network and exhanges data with the different types of PLCs. We can use the message routing capabilities of the Control Logix gateway to access pretty much any PLC in the entire system, simply by specifying the link ID of whatever link it is on and the node number of the PLC. This works all fine and dandy, except that it sits on the DH+ network which is a bottleneck. So, we're trying to do the same thing over ControlNet.
We can access local PLCs with no problem. However, when we try to go through the gateway from ControlNet to another network the only way we've figured out how to do it is that if we supply all of the routing information. We've done this and successfully routed to a PLC on a DH+ network from the ControlNet network. It seems kind of silly to have to configure all of the routing information in the Control Logix gateway, then configure all of the routing information again on our system, so what we're trying to do is take advantage of the routing tables in the Control Logix gateway. The ControlNet spec isn't much help. When I go into RS Logix, I can configure a message block that uses the link IDs, which looks like exactly what I want to do, except do it from our system instead of the PLC 5. If I could just figure out what a PLC 5 sends out when you configure it this way I'd be all set. Unfortunately, our PLC 5 is of too low of a revision and won't accept the message block.
So, what I'm looking for is info on how to send routed ControlNet packets using the link IDs set up in the Control Logix gateway's routing tables.
I hope this makes sense, and sorry if my terminology is a bit off.