How to configure modbus using Dasylab

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Hello All,
I am new to Dasylab. Anyone please show me how to configure modbus using Dasylab?
I am using Dasylab v9, and I am trying to use DasyLab to interact with a controller through Modbus serial communication.The Dasylab manual gives little help about this, and I can not read data from connected devices to the controller. If there is any solution for that then let me know how to do that.

Thank for your help.

[MHa]

Hello,

OK you use Modbus based on COMx interface, Modbus TCP/IP is not supported from DASYLab driver.

1: Check which IO type do you need, Analog Input, Output, Digital Input, Output.

2: for instance Analog Input, choose the Modbus device address, You can set this address with any software configuration program from Modbus hardware producer.

3: for instance Analog Input, go into the module dialog and there into setup dialog. Check which settings are require for Baud rate, Parity, Baud rate, Stop bits >> written into the manual from Modbus hardware producer.

4: Check the manual from Modbus hardware producer for address mapping informations, which register is used to read out analog input values from channel 0, from channel 1, from channel 2, ... This should be into the register area 30000 ... 39999. For instance 30001 >> then choose under DASYLab dialog Register 30 and 1 in the following edit field.

Best regards,
MHa

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mHa, Thank for the help

I am using pHD sc Digital Differential pH/ORP sensors from Hach. According to the manufacturer manual, the communication  is digital. However they also provide Modbus registers 40001 to 40007. I called Hach for support and they do not know anything about Dasylab.

If it is the Modbus digital Input, what should I enter in starting byte edit field?I already tried this with some number came up in my mind just to see how it respone, and it gave me weird and invalid numbers.

Since they provide me Modbus Registers table, I also tried Modbus analog input. The test results has scaled data and raw data. These number did not make sense to me.

I used Simply Modbus 6.0.1 software to read the registers, it gave me correct number what i was measuring.

Any suggestion?

[MHa]

Hello,

you need the detail COMx settings to configure into the Modbus setup dialog. Otherwise your COMx communication is broken. You get this information only from your Modbus hardware producer.

The DASYLab Modbus driver supports

0x01 Read Multiple Coils; used via Digital Input module
0x03 Read Holding Register 40000; used via Analog Input module
0x04 Read Input Register 30000; used via Analog Input module
0x0F Force Multiple Coils; used via Digital Output module
0x10 Write One Register Value; used via Analog Output module

Digital Input - starting byte is the possibility for byte shifting into the row data and select the interesting area for the module instance. For general check and learing you can use the "MODBUS Serial RTU + TCP/IP Simulator" http://www.codeguru.com/Cpp/I-N/network/serialcommunications/article.php/c5401

Best regards,
MHa