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Modbus I/O server: a small bug

Dear NI support,

this post is for to signal a bug in the Modbus I/O server available in the RT and DSC module.
Through the  "View I/O Items" it is displayed a list of available "I/O items". The list includes the standard Modbus register as Coils, Discrete Inputs, Holding Registers and Input Registers.
For each entry of the "I/O items" are shown three information area: "Item data type", "Item access type" and "Item description".
1-
For  Holding Registers (3xxxxxx) the "Item data type" displays a double-precision number and "Item description" displays "Access 16-bit input registers encoded as unsigned integers ranging from 0 to 65535."
The Modbus standard defines the Holding Registers as 16-bit word,  the "Item description" is correct and the "Item data type" is faulty.
When shared variable is linked to a  Holding Register, the shared variable became a double precision number, this is faulty and misleading for the user.
2-
For  Input Registers (4xxxxxx) the "Item data type" displays a double precision number and "Item description" displays "Access 16-bit input registers encoded as unsigned integers ranging from 0 to 65535."
The Modbus standard defines the Input Registers as 16-bit word,  the "Item description" is correct and the "Item data type" is faulty.
When shared variable is linked to a Input Registers, the shared variable became a double precision number, this is faulty and misleading for the user.
3-
The bug is present in the Modbus I/O server both Slave and Master.

I attach a screen shot of "View I/O Items" panel both for  Holding Registers and  Input Registers.

Regards,
Asper
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Grazie per l'importante feedback.
Ho provveduto a passare l'informazione alla ricerca e sviluppo.
Distinti saluti,
Giuseppe
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