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Read values between two resources [message #1863243]

Fri, 19 January 2024 11:37

Eclipse User

Hello, I have an application in which I want to read the AD value of a microprocessor pin and send it to another resource that is connected to the same device. I used Publish and Subscribe, but I have encountered the INVALID_ID subscribe error. In the attached images, I show my system with FORTE_PC and 2 resources (EMB_RES and EMB_RES1), sending via Publish and receiving via Subscribe. I don't know why the value didn't appear in the other resource. Thank you very much in advance.

Attachment: System_Configuration_FORTE_PC_2_resources.png
(Size: 42.01KB, Downloaded 92 times)
Attachment: Publish_value.png
(Size: 60.25KB, Downloaded 76 times)
Attachment: Subscribe_in_other_resource.png
(Size: 36.02KB, Downloaded 81 times)

Re: Read values between two resources [message #1863245 is a reply to message #1863243]

Fri, 19 January 2024 11:53

Eclipse User

unconnected publish or subscribe blocks are not allowed. Do you get any log messages. Between two different resoruce you may also want to have a look at our local comunication layer. There should be something in our documentation on it.

Re: Read values between two resources [message #1863247 is a reply to message #1863245]

Fri, 19 January 2024 11:59

Eclipse User

Ok Alois, i will search in documentation. Thanks for the help.
When i said unconnected publish or subscribe blocks, its about the system without ethernet?

[Updated on: Fri, 19 January 2024 12:00] by Moderator

Re: Read values between two resources [message #1863250 is a reply to message #1863247]

Fri, 19 January 2024 12:02

Eclipse User

No I meant that the output pin RD_1 was not connected. Therefore the publish block does not know anything about the type.

Re: Read values between two resources [message #1863253 is a reply to message #1863250]

Fri, 19 January 2024 12:20

Eclipse User

I connect an output in RD_1 pin. But the INVALID_ID continue.

Re: Read values between two resources [message #1863254 is a reply to message #1863253]

Fri, 19 January 2024 13:24

Eclipse User

Alois. i made a test running with forte.exe directly and i observe the value with the two resources work normally. In the case, to run embedded, there's something related to compilation that can cause the problem?

Re: Read values between two resources [message #1863255 is a reply to message #1863254]

Fri, 19 January 2024 13:41

Eclipse User

in order that this works you need UDP multicast support and for Subscribe espeically ICMP join messages. It could be that you don't have that. Then definitly the local layer is the better option.

Re: Read values between two resources [message #1863280 is a reply to message #1863255]

Mon, 22 January 2024 14:55

Eclipse User

Hello Alois, do you talk about ICMP or IGMP?

Re: Read values between two resources [message #1863293 is a reply to message #1863280]

Wed, 24 January 2024 06:09

Eclipse User

Oh sorry I meant IGMP.

Re: Read values between two resources [message #1863296 is a reply to message #1863293]

Wed, 24 January 2024 09:24

Eclipse User

Hello Alois, one more question. When I create PUB and SUB, I create a UDP connection between them. If I run it on the local FORTE, does it create a "virtual" UDP communication to send between the PUB and the SUB? I tested running the microprocessor project on a MAC OS to see if the SUB updated the RD_1 value, but still without success. Then I want to understand this part of UDP communication so I can check if my microprocessor is not executing this part correctly. When I did the debug, it creates the communication and also initializes IGMP. I just need to better understand this stage of communication.

In the image you can see the communication in my microprocessor and the UDP. The problem is the microprocessor don't receive the package.

Thanks.

Attachment: Communication_UDP.png
(Size: 9.70KB, Downloaded 83 times)

[Updated on: Wed, 24 January 2024 09:41] by Moderator

Re: Read values between two resources [message #1863297 is a reply to message #1863296]

Wed, 24 January 2024 09:58

Eclipse User

If you are not specifying an specific communication layers (please see our communication documentation) it will always fall back to UDP multicast. If you want to receive communication locally normally you need to have a loop back device and loop back routes configured.

However we also offer other communication protocols as stated above. If you just want to communicate between two resources on the same device you can for example use the shared memory local communication layer for this you can specify

loc[id]

as parameter for your publish or subscribe block. id is a unique string that have to be the same for both your publish and subscriber pair.

Re: Read values between two resources [message #1863301 is a reply to message #1863297]

Wed, 24 January 2024 12:07

Eclipse User

Thanks Alois, worked.

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