ObjectType: Available Object Types to be Read/Written
The ObjectType enumerated data type contains the object types that are available for reading and/or writing.
The table below lists the data type values, the corresponding object types and the Modbus request function codes associated with each function block:
|
|
Read / Write Functions and associated Modbus Request Function Code |
|||||
|---|---|---|---|---|---|---|
|
Enumerator |
Value (hex) |
Object Type) |
READ_VAR |
WRITE_VAR |
SINGLE_WRITE |
WRITE_READ_VAR |
|
MW |
00 |
Holding Register (16 bits) |
#3 (Read Holding Registers) |
#16 (Write Multiple Registers) |
#6 (Write Single Register) |
#23 (Write-Read Multiple Registers) |
|
I |
01 |
Digital Input (1 bit) |
#2 (Read Digital Inputs) |
— |
— |
— |
|
Q |
02 |
Internal bit or Digital output (coil) (1 bit) |
#1 (Read Coils) |
#15 (Write Multiple Coils) |
— |
— |
|
IW |
03 |
Input register (16 bits) |
#4 (Read Input Registers) |
— |
— |
— |
