Hi all,

sorry for joining in the party late ... but hopefully not too late.

Regarding making the serial port part of the connection string ... I have to 
admit that right now I couldn't imagine how to not have it in there and not 
over-complicate things for the users. Yes, if you create a connection this will 
have exclusive handle to the port, but this is actually an important thing to 
have. In contrast to network devices that can handle multiple connections in 
parallel ... a serial port is ... well ... serial. Havin asynchronous access to 
one serial port from multiple areas in an application sound like a bad Idea. 

However you could always use the connection pool ... in this case the pool 
would have one connection open and could share this (serially) with multiple 
parts of an application. Here a part would request the connection, do its work 
and then give the connection back to the pool where another part of the 
application could use it. This way I think we have the ideal tradeoff between 
sharing a connection and not having to be concerned about breaking the serial 
operation of the serial-port communication.

And yes: We could use some documentation on the connection pool ... and the 
scraper ;-/

Perhaps I'll whip up a little documentation on the connection-pool as I just 
recently had to find out how to use it myself ;-)


´╗┐Am 25.06.20, 11:41 schrieb "Julian Feinauer" <j.feina...@pragmaticminds.de>:


    yes, its in the module scraper or plc-scraper.
    Its easily configurable by yaml, json or programmatically.


    Am 25.06.20, 10:30 schrieb "Niclas Hedhman" <nic...@hedhman.org>:


        Another question; is there any "loop" system that just continuously 
        until I tell it to stop?

        On Thu, Jun 25, 2020, 15:16 Julian Feinauer 

        > Hi Nic,
        > I have to dig in a bit later to give you good answers but AFAIR the
        > connection can be left open and configuration should be as you wrote 
        > I also did some tests with it but that was some months ago...
        > Hope to have some more information later.
        > Julian
        > Am 25.06.20, 05:58 schrieb "Niclas Hedhman" <nic...@hedhman.org>:
        >     Hi,
        >     IIUIC, the connection string for Serial Modbus would be something 
        >          modbus:serial:/dev/ttyS0?unit-identifier=7
        >     assuming I want to communicate with device with address 7.
        >     That would mean that I have one connection per device I talk to 
over a
        >     single serial port. Is that correct? (Personally, I would not 
made the
        >     device part of the connection abstraction, but realize that it is 
a bit
        >     late for that)
        >     Are there any issues here, regarding which connection has access 
to the
        >     port, or do I need to open and close the connection on each set of
        > messages?
        >     Couldn't find info about this in the documentation.
        >     The serial port page is missing information on the configuration 
        >     parity, stop,...). The source code doesn't have the
        > @ConfigurationParameter
        >     annotations, so will they still work or do I need to add that
        >     programmatically somehow?
        >     Cheers
        >     Niclas

Reply via email to