The Industrial Raspberry Pi Forum

Hello
I am working on RS485 chain on Pictory and used 150 Input RTU Master block. This block has 150 Input Words and 32 of each Output Word, Input Bit and Output Bit, therefore total 150+32*3 = 246 inputs and outputs. However, when I was entering the addresses in 'Extended Data' after right clicking the block; it was limited to only 32 total inputs and outputs. I have total 119 Inputs and Outputs, used in my LogiCAD program. Can you please advise some way so that I can use all my I/O?
Thank You

Hello Alamdar,

1. please open the 'Extended Data' dialog window by right-clicking on your Modbus Master 150 device
2. in the 'Function Code' column please select 'READ_INPUT_REGISTERS'
3. in the 'Device Value' column you now have a list of all your 150 Input_Word values

Please give me feedback if this advice worked for you ...

Regards,
Frank

Hello Frank
Thanks for looking into this. The 'Device Value' provide all the I/O available at Modbus block however the column 'Action ID' is limited to only 32 rows. After 32rows when I click 'Add Row', it gives me error as in the below image. How can I use all device values of the block if action ID is limited.

Hello Alamdar,

ok, this was a missunderstanding: normally the number of action rows you can add is limited to the number of Action_Status values the device offers.
Under certain circumstances this limitation could be switched off - I'm currently discussing this issue with our Modbus-Expert in the company ...

We will probably offer you a solution for this special case in short-term.

Greetings,
Frank

Hi alamdar.syed, there are some adjacent registers. You can combine them with a single action. I.e. rows 14 and 15 may be combined with by reading two registers starting at 53507.
This also applies for rows 30 and 31, etc. This combination of adjacent registers increases the performance of your system. So by doing this combined actions can you estimate that you need more than 32 actions anyway?