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Brooks SmartDDE communication problem

I'm using SmartDDE software to control 8 digital MFC (Brooks 5850s) by using two 0154 Brooks control unit through RS232.
I'm able to open both Com Port and all eight channels with following Tag name: CHANNEL1...CHANNEL8.
The first four channels function properly while the last four channels doesn't function properly.
If I try to do a read from DMFCs by using Excel I can open the conversation number and the item advise loop for all channels  but I can read only from the first four channels; the requests on the last four channel generate a timeout.
Can you help me to know how I can communicate within 8 DMFC by using two 0154 control unit and SmartDDE software?
I think it could be a Topic name configuration problem but I didn't find anymore on related operation manual.
Thank you in advance.
Best regards.
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Message 1 of 29
Hi, I found a couple of forum talking about the same meters you are dealing with, maybe these information could be useful for you.
If you need something else I believe you'd beter ask Brooks.

Regards. NicolaC.
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Message 2 of 29

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

Retired Senior Automation Systems Architect with Data Science Automation LabVIEW Champion Knight of NI and Prepper LinkedIn Profile YouTube Channel
Message 3 of 29
Control units 0154 I'm using to talk with DMFC are able to communicate with SmartDDE separately; the problem is the tag name of four channels on each unit.
The default setting names each channel as Channel1, Channel2 .. Channel4; but if I use two unit 154, SmartDDE can't communicate with channels 5 to 8, it reads only the first four channels.
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Message 4 of 29

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. 

Michael Munroe, CLD, CTD, MCP
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Message 5 of 29
Yesterday I have received from Brooks technical support the application for the reconfiguration of the 0154.
It is a simple program that rename the Tag name of each channel in 0154.
Anyway I have yet  resolved the problem following the instruction of Brooks technical support; I rename manually the tag name
by using the relative Item# cited in the SmartDDE Operation Manual (more precisely the Item #12).
It was enough to rename each channel from CHANNEL1 to CHANNEL5 and so on until CHANNEL8.
I used a simple communication program in labview to read/write a specific Item# on a specific com port.
I was very surprised by the simpleness of the solution and the prompt answers of the Brooks technical support.
However I want to thank you all for your replies and I hope it can be useful for anybody that has the same problem.

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Message 6 of 29

Thanks for the update!


Retired Senior Automation Systems Architect with Data Science Automation LabVIEW Champion Knight of NI and Prepper LinkedIn Profile YouTube Channel
Message 7 of 29
Re: Brooks 0152/0154 MFC control box, does anyone have the RS-232 protocol and command set ?

Does the manual for the Brooks 0152/0154 "Gas and Liquid Mass Flow Secondary Electronics", ie, the box you manually power and control 2 or 4 MFCs through, describe the RS-232 commands to put set point (SP), read the present flow (PV), etc. ? A research group here has 3 Brooks 0154 boxes, and I would much rather talk RS-232 to them than wire up 12 AO and 12 AI to manage these flows. I don't want to mess with a DDE, the grad students have lost all three manuals, and I just need the baud, bits, parity, handshake, and command and response sentax. Any help appreciated.


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Message 8 of 29

Hi David,

"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.



Retired Senior Automation Systems Architect with Data Science Automation LabVIEW Champion Knight of NI and Prepper LinkedIn Profile YouTube Channel
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Message 9 of 29
We have all analog 5850E MFCs. Since Brooks claims the same 0152/0154 boxes  are compatible with both their analog and digital MFCs, the 0154 box commanding analog MFCs converts commands received on the RS-232 port via DA to 0-5 VDC analog out for set point, and reads back flow via 0-5 VDC AD to report back the process value to the command host.

If I had the digital MFCs, there would be no 0154 box at all, just a power source, and an RS-485 daisy chain.

In our application, we are resource constrained, and using the 0154 box as a serial connected DA/AD system benefits us. We have a fully stuffed pc backplane with just a few unused DIO AI and AO, we can't afford more hardware or an external bus system like FieldPoint, and must make do within these constraints. I will have to share the RS-232 port for several purposes other than gas flow control. Does the DDE from Books allow other data streams access on the same COM port ? I doubt it.

Chatting with serial devices is easy in general, a bit challanging in LV since you don't have facile raw device access, but doable. 35 years experience helps, too. If you want a serial IO challenge, try the Dallas Semi 1-Wire family of serial bus devices from straight LV !

So, back to the question: Brooks 0152/0154 commands and protocol ?

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Message 10 of 29