[etherlab-users] Read from/write to the slave's object dictionary using SDOs

Mohsen Alizadeh Noghani m.alizad3h at gmail.com
Wed Sep 26 11:55:54 CEST 2018


Thanks.

I tried the second option (used ecrt_master_sdo_download) and it worked.

Best,
Mohsen




On Wed, Sep 26, 2018 at 2:45 AM, Gavin Lambert <gavin.lambert at tomra.com>
wrote:

> There’s a number of different ways to do it, depending on why and how you
> want to do it.
>
>
>
> If this is a configuration setting (especially if it needs to be re-sent
> every time the slave reboots) that you can write (without needing to read
> anything), then you should use one of the ecrt_slave_config_sdo*()
> methods.  This will not do it immediately but will do it when you activate
> the master, and also if the slave reboots at any time while the master is
> active.
>
>
>
> If it’s a one-off request/query which you only do before activating the
> master, then you should use one of the ecrt_master_sdo_*() methods.  This
> will execute immediately and wait for the response.
>
>
>
> If you want to do it while the master is active, then you can either call
> ecrt_master_sdo_*() from a separate (non-realtime) thread (at the cost of a
> little extra latency on the realtime cycle), or you can use
> ecrt_slave_config_create_sdo_request() and related methods to perform
> polling on the realtime thread (for some extra code complexity).
>
>
>
> If it’s just something you need to do during commissioning and then never
> again (eg. if you can save the setting to the slave permanently), then you
> can use the “ethercat download” command.
>
>
>
> *From:* Mohsen Alizadeh Noghani
> *Sent:* Wednesday, 26 September 2018 03:41
> *To:* etherlab-users at etherlab.org
> *Subject:* [etherlab-users] Read from/write to the slave's object
> dictionary using SDOs
>
>
>
> Hello everyone.
>
>
>
> How can I read from or write to an entry of a slave's object dictionary
> using SDO? I'm going to do this before my real-time task.
>
> For example, I would like to set the value of 0x6040 to 15 before my
> cyclic task.
>
>
>
> Best,
>
> Mohsen
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.etherlab.org/pipermail/etherlab-users/attachments/20180926/b923d222/attachment.html>


More information about the etherlab-users mailing list