Author Topic: Two MCU's  (Read 5601 times)

glouw

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Two MCU's
« on: December 10, 2014, 05:59:00 PM »
We need to use a DP720 display to display the information from two analog sensors. The two sensors are separated from one another by some distance, and the sensors themselves are separated from the display by some distance. Can we place one MC012-112 next to each sensor and utilize a CAN bus to transmit the data to the display? Is this doable with PLUS+1 GUIDE?

Offline spittet

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Re: Two MCU's
« Reply #1 on: December 10, 2014, 07:17:07 PM »
I don't understand your problem with the "distance". Even if you put two MC012 between the sensors and the display, you will still need to run some wires for the CAN communication between the MC012 and the display. If wiring isn't a problem, then run both analog outputs from your sensors to the multifunction input pins on your Display and manage the analog to value conversion inside the Display program.

If you cannot run a lenght of wire between the sensors and the display, then you could use the MC012 to convert the analog outputs into CAN data and you could use a CAN to Bluetooth/Wifi bridge between your display and the MC012 to be wireless CAN.

Sam

glouw

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Re: Two MCU's
« Reply #2 on: December 10, 2014, 10:44:21 PM »
Hi Sam,

I suppose the motive for pairing MCU's with the sensors is to reduce wiring and prevent signal degradation. GUIDE will allow for a display to read data from two different MCU's over CAN, correct?

EDIT:
I'm overlooking this, Sam. Since the IO modules are CAN based, one of the controllers can be replaced with an expansion IO module, like an IX012-010. This answers my questions in regards to GUIDE programming.

EDIT2:
I'm still overlooking this, Sam. Both CAN controllers can be replaced with CAN expansion IO modules, like the IOx012-010. The display can be programmed via GUIDE to access the pins of the IO modules.
« Last Edit: December 11, 2014, 12:39:37 AM by glouw »

Offline spittet

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Re: Two MCU's
« Reply #3 on: December 11, 2014, 02:15:59 PM »
You are right on all points. I didn't think about the Input/Output Expanders.

Also, yes, you can use two MCUs on the same CAN network, assuming both MCUs have a different node ID. It's the same thing for both IO Expander, they must have a different node ID.

Sam

glouw

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Re: Two MCU's
« Reply #4 on: December 11, 2014, 06:59:13 PM »
Thanks for the help, Sam. Two MCU's sounds as if would complicate matters; GUIDE works beautifully if one plays by the rules.

-gus

Offline ZanInno

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Re: Two MCU's
« Reply #5 on: February 20, 2015, 07:00:01 PM »
There is not a limit to how many MC's can be on one network.  If you plan to connect to the network and program/diagnose the MC's with the Danfoss Service tool, then they all have to have a different node ID.

It would be a simple program for a MC12 to read and condition a signal, then broadcast the value out to other MC's or displays. I prefer to work with MC's rather than the I/O modules.  It gives you the ability to condition the signal as it is received and it keeps the bus traffic down to a reasonable level.