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Author Topic: Spindle Control Brain for Modbus  (Read 5803 times)

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Spindle Control Brain for Modbus
« on: March 11, 2010, 09:31:43 AM »
I am going to use Modbus Plug-in and an M13 expansion board (CNC4PC) to control the spindle speed of a VFD.  I have the control wires for the VFD connected to output 3 and GND of the Analog Out portion of the board.  Arturo mentioned the use of a brain to control this output.  I downloaded and installed Scott's ModSpinOutControl.brn.  Can someone help me understand the logic before I blindly start using it?  How would I state the address for the analog out?  In the brain file I put in 4007 and it says this value is not valid.  Should this value be 4 of configuration 3 instead?  A screenshot of my Modbus Configuration is shown below. 

Thanks
havery

Offline poppabear

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Re: Spindle Control Brain for Modbus
« Reply #1 on: March 14, 2010, 05:04:14 AM »
I will answer your questions, but, I highly recommend you read the "Brians Users Guide" in the member docs section on this forum, it will answer many of your questions.

Summer is this, you analog out is on Cfg #2, and if i under stand you correcly your saying out analog output is #3 on his board, which equates to local var #2, in the modbus (since the anlog local vars is 0-3 for physical outputs 1-4 of outputs).

so your output termination in serial modbus will be "Modbus Serial plugin, Cfg #2, var #2"
this assumes your modbus analog outputs is on cfg#2 and your using the 3rd of the physical (screw terminal), on the analog out put row.
the resolution of his analogs is 256 (8 bit).

so the Brian line/rung for spindle analog output reads like this:

Spin DRO 99 -> formula: A*255 -> Plugin serial modbus, output, cfg 2, var 2

scott


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