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Mitsubishi Q and SMC JXCD1 Devicenet module

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Hi guys.


On our company we got several different PLC system but right now I´m focusing on a Mitsubishi Q-system with device-net master QJ71DN91.   


We are going to make communication with SMC-JXCD1 controller for a actuator.   But I have no experience with DeviceNet and unfortunately there is no files, functionblock, or program examples what I can find.  Not even Mitsubishi or SMC had some for these two together so I turning the

Question into this forum instead😊


Previously I´ve used profibus on a fx3U system and FX5U-Simple CPU communication protocol to talk with slaves in a network. 


I got on hold of some old document from Beijer from where I got 3 functionblocks for devicenet. 



2. DnSupervisorQ

3. DnDataQ

4. DnMessageQ



So maybe I can have some help from these but I´m still not sure how to send/receive information to the SMC-nodes.   I´m a little confused about if I should use the master with I/O communication or  master with explicit messages?  The later I haven´t even heard of. 


I was only thinking about creating array of word to receive and send info to the nodes.  

But my knowledge of this communication protocol is very low.   



Anyone know´s how to get me started?  Or can provide some kind of example in GX IEC or GX works. 




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add card into PLC rack and note the head address.

perform correct DNET wiring and termination.


just like other fieldbus types:

a) all nodes are wired "in parallel" (hence the bus).

b) on the two extreme ends of the bus need suitable terminations (121 Ohm 1% resistors).

c) while it is possible to use trunk/drop style wiring, there are limitations, particularly on length of the drop. Preferred way is to have no drops.

d) all nodes need unique address or MacID

e) data exchange for the most part is cyclical (master is polling slaves). in rare instances there may be need for explicit message. normally this is used to configure slave or transfer large block of data that exceeds size of mapped IO blocks.


note unlike other bus types (ProfiBus etc.):

a) DeviceNet bus also has conductors for power and you need to provide that 24VDC (it is not something that is obtained internally).

b) terminating resistors are normally discrete components and resistor leads tend to be exposed - it is a good idea to add protection (i prefer clear heatshrink). On other busses they tend to be integrated into connectors or molded into suitable shape.

c) Unlike Profibus for example, bus speed settings is usually done at each and every node, although there are some products that can autodetect baud rate.


next part is software configuration. this means obtaining EDS for each slave. contact slave manufacturer to get them. according to JXCD1 manual, EDS can be downloaded from the SMC website:

i just glanced it and see IODD file for IO-Link but not EDS so perhaps specify exact product name (JXCD1S or whatever) or call tech support.

on second look, one just needed a minute or so do deeper search specifically for DeviceNet version and EDS file is found at:

or direct link

then the master need to be configured by building scan list. have not done this on Mitsubishi so cannot help much there. the idea is to add matching EDS for each slave to master configuration and parametrize it. in simplest case that means stating the node address but you may also need to specify size of IO blocks that node will send or receive.

Finally there will be some code. Normally this is just few lines to initiate data exchange and handle diagnostics (missing slave etc.) and of course do the data exchange between master and controller. Normally all of this (including code examples) is in the product manual. In Mitsubishi tradition, programming documentation tends to show examples for intelligent modules using head address zero and you would of course need to change it to match your PLC configuration. if you are new and confused by this, perhaps consider placing this module next to CPU.

for more help or interpreting data in the documentation, post the links to actual manual(s) so we don't need to look them up.




and AndreasW already posted link to Mitsi manual. 




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I have started to do some programming and wiring with the DeviceNet module and slaves. 

But today when i downloaded it into the Q-system i got error. I had forgot to change the "plc module" list so there was a "intelli" module on the correct head adress. 

But there is no way to find the  QJ71DN91 module in the list?   See attached pictures.   Program is GX IEC.    

Since the "help-document" was written and function blocks made in GX IEC there must be a way to have them in this environment.  



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Take you attention on the version of GX IEC, the last is 7.04. I'm thinking, to the 7.04 release the QJ71DN91 module was already in sales. Hope it will help you to solve the problem.

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