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Master/Slaver Simulation
New Replies:
By M Griffin on 1 September, 2009 - 2:57 pm -
What sort of Modbus are you looking for? RTU (RS-232/RS-485) or TCP (Ethernet)?
If you are...
I´m looking for free source code (or examples) of ModBus protocol in C or C++.
New Replies:
By M Griffin on 27 August, 2009 - 3:46 pm -
Have a look on Sourceforge for C Modbus libraries. ...
By curt wuollet on 27 August, 2009 - 9:43 am -
Modbus in vhdl? now, that would be interesting. They do have some C examples on Modbus.org, or did,...
By ankur bagul on 27 August, 2009 - 5:55 am -
I'm looking for free source code (or examples) of ModBus protocol in vhdl or C. I would like to...
What is a good DNP3 testing software?
Modbus communication problems with Telemeq. Altivar 31. AB micrologix 1400ML.
Return strings from Modbus simulator application differ from that of HVAC system harware
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By M Griffin on 14 August, 2009 - 1:38 am -
You haven't really given us enough information to go on. The most common problem that people have...
By Mark on 13 August, 2009 - 8:55 pm -
Hi,
I do not see enough information to determine exactly what is wrong. One thing I do see is...
It is not unusual to have byte reversal issues. One of the devices, Host or Slave, should have a...
By Carl on 13 August, 2009 - 8:41 pm -
The register number could be off by a one, depending on whether the registers are numbered from...
how a flow meter communicate
New Replies:
By vahid on 12 August, 2009 - 4:27 pm -
Thank you for your reply.
I have the Fc config,the FC config can only read the data from one...
You need to go to the Emerson Mobrey website and download one of the Windows based programs such as...
I believe that you will need two pieces of software... one for data collection/communication via...
By vahid on 31 July, 2009 - 3:41 pm -
Scadametrics:
Our flow computers (7955) do have the serial port which supports the Modbud RTU,...
zabee,
If you wish to interrogate totalization and flow rate from water meters, then my company...
Vahid,
The 7955, depending upon which communication options it has, may support MODBUS/RTU or...
By Vahid on 30 July, 2009 - 11:11 am -
Our flow computer is Mobrey 7955, and the fluid is Crude oil, the floe element is orifice. I want...
By vahid on 30 July, 2009 - 11:07 am -
I have the similar case. I had some flow computers that I want some of their data and monitoring...
What is the brand and model of the flow meter? And what is the flow meter monitoring (water, gas,...
I think you are saying you need to convert pulses from the flow meter to an accumulator that...
By Andrzej on 29 July, 2009 - 9:03 am -
Hello,
You can add simply microcontroller like PIC with modbus slave protocol (see...
Program in CoDeSys for configuring communication between wago PLC modbus/TCP and many slave devices via RS485 module.
New Replies:
By Jan on 28 July, 2009 - 4:02 am -
Hi AuthorP,
can you send me please your Modbus/RTU program also? Email - jan233321 /at/...
By VijayaKumarM on 15 July, 2009 - 7:23 am -
Dear AuthorP
Can you plz send me the Modbus RTU library/program in codesys to my mail ID.
...
How to map variable length data to holding registers?
New Replies:
Now, that took me some time! But I have defined the registers (and am very glad that's finally...
By M Griffin on 19 July, 2009 - 3:14 am -
I will start off by saying that what would probably help a lot is to sit down and imagine yourself...
By M Griffin on 16 July, 2009 - 12:39 am -
You said that you're not sure about "the max data length of many variables". They're 32...
Modbus Connection AB CompactLogix - Mitsubishi A2ACPUcomm
New Replies:
By James on 23 July, 2009 - 9:28 am -
Yes, we want to use compactlogix as a master then Mitsubishi A2ACPU as a slave. Do you mean that we...
Is it possible to convert Modbus via TCP into Modbus TCP?
New Replies:
Hello,
I know a device which is exactly designed for your requirement, so from-to Modbus RTU...
how modbus tcp to rtu converter works
New Replies:
By Paul Wacker on 21 July, 2009 - 12:52 pm -
KK -
Modbus/TCP protocol includes a "slave address" field in the header. So, there is...
By kk on 21 July, 2009 - 1:31 am -
Dear Paul,
modbus TCP access the slave by ip address of that slave and modbus rtu access data by...
By M Griffin on 20 July, 2009 - 3:22 pm -
Modbus/TCP and Modbus/RTU are essentially the same protocol. The difference is that with RTU a...
By Paul Wacker on 20 July, 2009 - 1:38 pm -
KK -
There are two primary functions that these unit perform.
First, due to difference in the...
Need a Modbus RTU Master OPC Server as "Program Master"
New Replies:
Do you have the info how to setup those "Progam Master" paths on MB Plus? Sounds to me...
"Program Master" and "Data Master" are Modbus-Plus terms. Modbus-Plus supports...
seven Flow computers 7950 over a MODBUS network
OPC Server Hanging at will
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By UTR on 2 July, 2009 - 10:45 pm -
Having used both Matrikon and Kepware for similar applications I would reccomend moving to Kepware...
By Fred Loveless on 30 June, 2009 - 5:29 pm -
Try KepserverEx (http://www.kepware.com). We have and extensive posotive history working with...
By Mark on 30 June, 2009 - 10:11 am -
Hi,
The list of possible problems is very long. Without more data, finding the problem and...
What is the MODBUS RTU PROTOCOL format for ODD PARITY?
New Replies:
Parity is redundant and never normally used WHEN CRC error checking is implemented. Parity is not...
Configuration Modbus Slave TCP/IP on Citect Scada ver.7.0
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By Ian Finlay on 1 July, 2009 - 2:12 am -
You should probably look at MODNET rather than MBSlave. MBSlave was only meant for serial comm's....
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