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Read values between two resources [message #1863243]

Fri, 19 January 2024 16:37

André Soçva

Messages: 88
Registered: November 2023

Member

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 28 times)
Attachment: Publish_value.png
(Size: 60.25KB, Downloaded 26 times)
Attachment: Subscribe_in_other_resource.png
(Size: 36.02KB, Downloaded 25 times)

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

Fri, 19 January 2024 16:53

Alois Zoitl

Messages: 1589
Registered: January 2014

Senior Member

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.

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

Fri, 19 January 2024 16:59

André Soçva

Messages: 88
Registered: November 2023

Member

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 17:00]

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

Fri, 19 January 2024 17:02

Alois Zoitl

Messages: 1589
Registered: January 2014

Senior Member

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

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

Fri, 19 January 2024 17:20

André Soçva

Messages: 88
Registered: November 2023

Member

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

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

Fri, 19 January 2024 18:24

André Soçva

Messages: 88
Registered: November 2023

Member

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?

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

Fri, 19 January 2024 18:41

Alois Zoitl

Messages: 1589
Registered: January 2014

Senior Member

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.

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

Mon, 22 January 2024 19:55

André Soçva

Messages: 88
Registered: November 2023

Member

Hello Alois, do you talk about ICMP or IGMP?

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

Wed, 24 January 2024 11:09

Alois Zoitl

Messages: 1589
Registered: January 2014

Senior Member

Oh sorry I meant IGMP.

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

Wed, 24 January 2024 14:24

André Soçva

Messages: 88
Registered: November 2023

Member

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 22 times)

[Updated on: Wed, 24 January 2024 14:41]

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

Wed, 24 January 2024 14:58

Alois Zoitl

Messages: 1589
Registered: January 2014

Senior Member

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