The ClearSCADA Simple Modbus Driver supports several Modbus function codes, enabling it to read and write data on Modbus devices. The function codes that the ClearSCADA Simple Modbus driver supports are:
| Modbus Function Code | Functionality |
|---|---|
|
FC1 |
Read output coils |
|
FC2 |
Read input discretes |
|
FC3 |
Read multiple holding registers |
|
FC4 |
Read input registers |
|
FC5 |
Write coil |
|
FC6 |
Write single register |
|
FC15 |
Write multiple coils |
|
FC16 |
Write multiple registers |
|
FC65 |
Read S600 flow computer single-precision registers |
|
FC67 |
Read S600 flow computer double-precision registers |
An exception error is generated if an unsupported function code is received by a Modbus device (see Modbus Exception Errors).