I have developed a couple of aplications that used Brooks MFC's both dumb and smart using the 154 and not.
If I remember correctly you need to use the 154E with the emphesis on the the "E". The other 154's will not talk to SmartDDE.
You should really start by talking to Brooks about getting the the MFC's to work using their software.
The app's I have devloped used the SamrtDDE services or were controlled using FieldPoint AO and AI. The FP version was much easier to devlop and deploy. The SamrtDDE versions were more powerful and let you query the MFC's gas types etc.
Message Edited by Ben on 01-28-2006 10:32 AM
I ran into this same problem several years ago. Brooks technical support was no help. Later at Semicon, I complained to the regional sales manager that this was an unsolved problem that must plague many users. He promised to look into it. A few days later I received an email from from a Brooks engineer with a special utility application. It seems that you need this utility to reconfigure the second unit to respond to channels 5 to 8. Contact Brooks engineering to get the code.
BTW, since the SmartDDE program was unreliable for frequent, long-term process control, we replaced it with hard-wired analog I/O.
"I don't want to mess with a DDE,"
I am curious. Why not?
I have a customer that has been using the SmartDDE interface 24X7 for four years now. There was at least one update implemeted in that time period to fix some lock-up issues. Updates are not going to be incuded if you write your own interface.
You did not mention which type of MFC you were using.The SmartDDE interface comes with the Brooks software used to manage the Smart MFC's.
Brooks supplies an example VI to use ther DDE interface.
Their documentation includes the DDE spec.
I have never seen any docs from Brooks to answer your questions. They may have changed the support strategy since I last worked with them. I suggest you contact Brooks directly.