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Profibus - MB vector length 128 BYTES?

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In help entry of "Profibus Configuration" block (Home > Communications > PROFIbus Slave) it says that I can have a MB vector from which the master will read bit data, and another MB vector where the master will write bit data.


Both are documented as "Vector length = 128 bytes".

Is that 128 bits, or

128*8=1024 bits?

I don´t have the means to test it by myself....




Also, the "Profibus Configuration" block is connected directly to network.

Just to make sure, I don´t need an SB2 "PowerUp bit" contact like many other initialization blocks of Visilogic?




Can I have a CLP work with Profibus, Ethernet AND serial, depending on which board is installed?


Use SB178 "Profibus Card Detected" to enable "Profibus Configuration"

Use SB141 "Ethernet Card Detected" to enable  "TCP/IP CARD INIT", "PLC NAME", "Modbus IP Config", "Modbus IP Scan32"

None of the above to enable "COM Init", "Modbus Config", "Modbus Scan32"






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The vector for the MB/XI's is correctly listed as 128 bytes, which is 1024 bits.


The ProfiBus configuration should be a power-up task, running off of SB 2 and should not be directly called each scan.


With our V130 and V350 controllers it is possible to add one additonal port for CANbus, and/or another port for Serial/Ethernet/ProfiBus. It is unfortunately not possible to use both an Ethernet and ProfiBus card simultaneously due to hardware limitations.


Please know that as long as a card can be installed, it will operate independently from any other communications module (eg. It is possible to have both serial and Ethernet communications running simultaneously).

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Thanks, Alexander.


Before I post the question, I looked the help entry for the "Profibus Configuration" block, and it does not show the SB2 contact.

I found it strange and decided to ask the forum.



Today I updated the firmware of a V350, and Visilogic 9.7.9 prompted me if "will I use a Profibus card or not".

I also updated the firmware of a V130, but it didn´t ask me about the Profibus card.


The idea is to have an "auto configurable" CLP, which detects what card is present (with SB141 and SB178) and call the right initialization / protocol scan routines.


As I just saw, for V350 it is required to load the proper firmware - with Profibus card or not - so it´s not so "auto configurable" as I would like..



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You are correct, in order utilize the Profibus card a specific O/S will have to be utilized. However,using both SB 2 and either SB 141 or SB178 in series you can  initialize any required communications. This will allow for a single program to be written for the project, and when the hardware is detected it will initialize the proper function blocks (as long as the correct O/S is installed).

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My customer is saying that when he connects the V100-17-PB1 card (profibus) in his V130-33-T2, the screens goes black and CLP does not work.

When he removes the card, things get back to normal.

I have already upgraded the CLP firmware to latest version with Visilogic 9.7.9.

I did not test it connected to serial, to see if I can operands, etc.


The program is using SB141 to call ethernet routines only if ethernet card is present.

It is also checking a configuration bit to call (or not) COM2 init, but flag is cleared (no COM2 installed)

The program has no Profibus init routine at all.


I even checked for other O/S files, but I only have "VCO00300906_V130.UOS" in my "C:\Program Files (x86)\Unitronics\Unitronics VisiLogic_979_1\Data\Os\Vision Enhanced\V130\OS" directory.


Is there anything else to be done?

The "www.unitronics.com/docs/v130/v100-17-pb1_tech-spec_06-11.pdf?sfvrsn=2" does not mention any additional setting..




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Hello Amir,


Please ensure you have the latest OS by navigating to the help menu in VisiLogic, "Check for Updates", and choosing the "Operating System" option. This will connect to the internet and ensure you have the latest OS's and update them if not.


I would also suggest placing the unit into bootstrap mode (hold the (i) button on the controller while applying power to the unit to perform this update) with the profibus card attached. Then perform the OS update.

This should ensure the controller gets the firmware update.

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