CANopen communication, error NO_FREE_COBID_TABLE_ENTRY

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1

One of our customer is using demo of AsCANopen, returns an error of NO_FREE_COBID_TABLE_ENTRY. The sending COBID is set as 16#202, the receiving COBID is set as 16#182. How should we help him deal with the error?
Thank you

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2

Hi,

in your screenshot it looks like that the CANopen slave is already configured with Automation Studio (the slave “Lexium 32M”).

As I understand the following information out of the sample help, only exclusive use is possible: either configuring the slave via Automation Studio, or using the read/write functions of AsCanOpen for PDOs.

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Best regards!

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3

As @alexander.hefner mentiones the COB ID is registered within the system and must be unique.
If you configure the slave via Automation Studio the COB IDs for PDOs are registered by the system task handling CanOpen.
If you now try to register them again with the function blocks from the library you will get this error

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4

Hello,

I have one more question, if we use AsCANopen library to read/write PDOs, then we can not config the channel (as it will conflict), how do we mapping objects to PDO? (like the picture below), can library have such function to do mapping?:

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5

Mapping is done via SDOs (service data objects). The library incudes function blocks to read and write SDOs - “CanOpenSDOWriteData” for example.

Any CanOpen slave normally offers Objects called “PDO mapping”. Basically you need to write to this parameter the Objects which need to be transferred. In other words you write the value of the PDO parameter to this mapping parameter.
In order to do this you need to know the slave which means you have to have at least the EDS file and a description of the available PDOs and SDOs the slave offers.

Please also note that writing the mapping is not the only thing you need to do when not using the EDS file. It means you also have to configure the slave in terms of necessary parameters.
This is normally done when using the EDS file within Automation Studio but as you are asking how to map PDOs I rather think you do not use the EDS file now

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OK, Now we can make through this, Thanks!