Hi Julian,

Currently I have no idea if the modbus part still works after the refactoring 
(maybe Chris can help here) [might be disabled at all at time]. Before the 
register got mapped into the requested java type.
Regarding multiple items: like in ads the support for multiple items is 
currently not implemented so you would require to send a new request:
https://github.com/apache/incubator-plc4x/blob/master/plc4j/protocols/modbus/src/main/java/org/apache/plc4x/java/modbus/netty/Plc4XModbusProtocol.java#L79
 
<https://github.com/apache/incubator-plc4x/blob/master/plc4j/protocols/modbus/src/main/java/org/apache/plc4x/java/modbus/netty/Plc4XModbusProtocol.java#L79>

Sebastian

> Am 18.09.2018 um 08:21 schrieb Julian Feinauer <[email protected]>:
> 
> Hi Sebastian,
> 
> thanks for the fast reply, so the 16 bit register can be fetched as byte 
> array?
> And if I need two registers (should be a 32 bit value altogether) I put two 
> items in the builder?
> 
> I just looked at our test code from marcel and its like
> 
> PlcReadRequest plcReadRequest1 = new PlcReadRequest();
> //            ReadRequestItem<byte[]> readRequestItem1 = new 
> ReadRequestItem<>(byte[].class, 
> ReadInputRegistersModbusAddress.of(ADDRESS_PREFIX + 
> modbusAddressToKafka.getAddress()), 2);
> //            plcReadRequest1.addItem(readRequestItem1);
> //
> //            CompletableFuture<PlcReadResponse> completableFuture1 = 
> plcConnection.read(plcReadRequest1);
> //
> //            PlcReadResponse plcReadResponse = 
> completableFuture1.get(TIMEOUT, TimeUnit.MILLISECONDS);
> //            Optional<ReadResponseItem<byte[]>> ret1 = 
> plcReadResponse.getValue(readRequestItem1);
> //            if (ret1.isPresent() && ret1.get().getValues().size() == 2) {
> //                ByteBuffer byteBuffer = ByteBuffer.allocate(4);
> //                byteBuffer.put(0, ret1.get().getValues().get(0)[0]);
> //                byteBuffer.put(1, ret1.get().getValues().get(0)[1]);
> //                byteBuffer.put(2, ret1.get().getValues().get(1)[0]);
> //                byteBuffer.put(3, ret1.get().getValues().get(1)[1]);
> //                return byteBuffer.getInt();
> //            } else {
> //                throw new ModbusReadException(TIMEOUT_ERROR_MSG + " " + 
> modbusAddressToKafka.getAddress());
> //            }
> 
> And I don’t like the byteBuffer part as we as client in this case should not 
> bother with stuff like that.
> 
> So after changing to the new API I build to requests for two subsequent 
> addresses (named with their address) and do:
> 
> ByteBuffer byteBuffer = ByteBuffer.allocate(4);
> byteBuffer.put(0, 
> response.getByteArray(Integer.toString(modbusAddressToKafka.getAddress()))[0]);
> byteBuffer.put(1, 
> response.getByteArray(Integer.toString(modbusAddressToKafka.getAddress()))[1]);
> byteBuffer.put(2, 
> response.getByteArray(Integer.toString(modbusAddressToKafka.getAddress() + 
> 1))[0]);
> byteBuffer.put(3, 
> response.getByteArray(Integer.toString(modbusAddressToKafka.getAddress() + 
> 1))[1]);
> return byteBuffer.getInt();
> 
> Or is there any simpler approach to this?
> 
> Best
> Julian
> 
> Am 18.09.18, 08:08 schrieb "Sebastian Rühl" 
> <[email protected]>:
> 
>    Hi Julian,
> 
>    Two bytes would be a register so you could read it like that 
> („register:7"):
>    
> https://github.com/apache/incubator-plc4x/blob/master/plc4j/protocols/modbus/src/test/java/org/apache/plc4x/java/modbus/ManualPlc4XModbusTest.java
>  
> <https://github.com/apache/incubator-plc4x/blob/master/plc4j/protocols/modbus/src/test/java/org/apache/plc4x/java/modbus/ManualPlc4XModbusTest.java>
> 
>    All in all it seems that this driver is only able to read one 
> register/coil at a time a would need some work after the refactoring.
>    Types of addresses can be found here: 
> https://github.com/apache/incubator-plc4x/tree/master/plc4j/protocols/modbus/src/main/java/org/apache/plc4x/java/modbus/model
>  
> <https://github.com/apache/incubator-plc4x/tree/master/plc4j/protocols/modbus/src/main/java/org/apache/plc4x/java/modbus/model>
> 
>    Sebastian
> 
>> Am 18.09.2018 um 08:01 schrieb Julian Feinauer 
>> <[email protected]>:
>> 
>> Hi all,
>> 
>> I am currently migrating some code to the new plc4j API and are a bit unsure 
>> what to do.
>> The current code is
>> 
>> PlcReadRequest plcReadRequest1 = new PlcReadRequest();
>> ReadRequestItem<byte[]> readRequestItem1 = new 
>> ReadRequestItem<>(byte[].class, 
>> plcConnection.parseAddress(someAddressStringHere), 2);
>> plcReadRequest1.addItem(readRequestItem1);
>> 
>> So we fetch 2 bytes from Modbus.
>> How do I tell him to fetch an array of length 2 in the new API?
>> 
>> Thanks!
>> Julian
> 
> 
> 

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