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From Christofer Dutz <christofer.d...@c-ware.de>
Subject Re: MODBUS over RTU configuration
Date Wed, 02 Sep 2020 15:43:56 GMT
Well the PLC4X folks have just recently started working on a new initiative: PLC4PY (All PLC4X
drivers in native Python implementations)

Unfortunately I'm consumed with my PLC4C ... if you want to join them ... they would be happy
about anyone helping.

But if you want to get rid of Python (which I can understand very well ;-) ) feel free to
stick to PLC4J, which is obviously the most mature PLC4X ecosystem.

Chris



Am 02.09.20, 17:38 schrieb "Alessio Bernesco Làvore" <alessio.bernesco@gmail.com>:

    Yes, in fact right now we are using a python edge system (written by
    ourselves) to connect, but i'd like to migrate it to java.
    We mainly interact with OPC-UA or ModBus devices but sometimes the latter
    are Serial 485 and so we need an RTU enabled driver.

    I'll constantly keep an eye on the list and I'll contribute to the topic,
    if I can give any help.

    Greetings,
    Alessio

    On Wed, Sep 2, 2020 at 5:33 PM Christofer Dutz <christofer.dutz@c-ware.de>
    wrote:

    > Hi Alessio,
    >
    > thanks for volunteering to help with testing ... as Otto will agree ...
    > testing stuff is sometimes a good thing to do ;-)
    >
    > Even if it's not highest priority for you, we should continue the
    > discussion as this issue will come up sooner or later.
    >
    > Chris
    >
    >
    > Am 02.09.20, 17:29 schrieb "Alessio Bernesco Làvore" <
    > alessio.bernesco@gmail.com>:
    >
    >     Hello Chris,
    >     thank you!
    >
    >     I'm currently using some exotic RTU devices, just for test, so mine is
    > a
    >     low priority question.
    >     Of course i'm fully available to test any release against those
    > devices.
    >
    >     Greetings,
    >     Alessio
    >
    >     On Wed, Sep 2, 2020 at 5:14 PM Christofer Dutz <
    > christofer.dutz@c-ware.de>
    >     wrote:
    >
    >     > Hi Alessio,
    >     >
    >     > welcome on this super-cool community list of ours :-)
    >     >
    >     > Unfortunately I have a little "uncool" news ... while working on the
    > new
    >     > drivers, it occurred to me that we currently are absolutely able to
    > run one
    >     > protocol over multiple transports, however if the transports require
    >     > different handling on the lowest level, we currently haven't got
    > that base
    >     > covered.
    >     >
    >     > We started discussing options on how to solve this problem, but the
    >     > discussion is ongoing ...
    >     >
    >     > Unfortunately I didn't update the documentation ... as I thought
    > we'd be
    >     > able to implement this sooner.
    >     >
    >     > Possibly the 0.6.x version of PLC4X could work as starting with
    > 0.7.0 we
    >     > have deleted all existing drivers and have replaced them with new,
    >     > generated ones and are still working on implementing all the
    > features the
    >     > old ones had. Unfortunately you seem to be the first person to ask
    > for
    >     > serial Modbus, so we hadn't prioritized that up too much.
    >     >
    >     > So for now .. please give the 0.6.1 a go (might have slightly
    > different
    >     > syntax and connection string) and join in on the discussion here on
    > the
    >     > list and possibly help us finish this ... as none of us have a serial
    >     > Modbus device, it's sort of tricky to implement a driver for it.
    >     >
    >     > Chris
    >     >
    >     >
    >     >
    >     >
    >     > Am 02.09.20, 16:50 schrieb "Alessio Bernesco Làvore" <
    >     > alessio.bernesco@gmail.com>:
    >     >
    >     >     Hi everyone,
    >     >
    >     >     i'm trying to complete some tests connecting a Modbus RTU device
    >     > (digital
    >     >     input converter).
    >     >
    >     >     The device is connected using a USB/485 converter, running with
    >     > pyModbus
    >     >     i'm able to communicate with the device.
    >     >
    >     >     I'm using this connection string:
    >     >
    >     >     PlcConnection plcConnection = new
    >     >
    >     >
    > PlcDriverManager().getConnection("modbus:serial:///dev/ttyUSB0?unit-identifier=1");
    >     >
    >     >     Then:
    >     >     PlcReadRequest.Builder builder =
    > plcConnection.readRequestBuilder();
    >     >     builder.addItem("value-0", "holding-register:14");
    >     >     PlcReadRequest readRequest = builder.build();
    >     >     PlcReadResponse response = readRequest.execute().get();
    >     >
    >     >     But i was unable to obtain a response, watching at the logs
    > there are
    >     >     plenty of:
    >     >     io.netty.channel.nio.NioEventLoop        : Migrated 1 channel(s)
    > to
    >     > the new
    >     >     Selector.
    >     >     Selector.select() returned prematurely 512 times in a row;
    > rebuilding
    >     >     Selector
    >     >
    >  org.apache.plc4x.java.transport.serial.SerialPollingSelector@37f2b566.
    >     >
    >     >     Another important part is that i'm unable to find where i can
    >     > configure the
    >     >     serial communication parameters, like baud rate, stop bits, etc.
    >     >
    >     >     Greetings,
    >     >     Alessio
    >     >
    >     >
    >
    >

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