The function block is used to read discrete inputs from an external device using the Modbus protocol (function code 0x02).
|
Input |
Data type |
Description |
|---|---|---|
|
i_xExecute |
BOOL |
A rising edge of the input i_xExecute starts the execution of the function block. Refer to Behavior of Function Blocks with the Input i_xExecute and i_xAbort. |
|
i_xAbort |
BOOL |
A rising edge of the input i_xAbort aborts the execution of the function block. Refer to Behavior of Function Blocks with the Input i_xExecute and i_xAbort. |
|
i_sServerAddr |
STRING[80] |
Address identifier for connecting to the external device.
The address is specified in the format
Values in square brackets are optional. If they are not entered, the default values
Example:
If the format or a value of an element is invalid, the error message |
|
i_timTimeout |
TIME (T#60s) |
Timeout for the operation. If the specified time expires during execution, the process is aborted. A value of T#0s deactivates the timeout monitoring in the function block. |
|
i_uiStartingAddress |
UINT |
Specifies the address of the first object to be read. The first object corresponds to the first item in the buffer. |
|
i_uiQuantity |
UINT |
Specifies the number of objects to be read. Range: 1...2000 If a value is not specified, the amount of objects determined by the buffer is taken into account. |
|
Input/Output |
Data type |
Description |
|---|---|---|
|
iq_axBuffer |
ARRAY[*] OF BOOL |
Array of Booleans, providing a buffer to store the read data. |
|
Output |
Data type |
Description |
|---|---|---|
|
q_xBusy |
BOOL |
If this output is set to TRUE, the function block execution is in progress. |
|
q_xDone |
BOOL |
If this output is set to TRUE, the execution has been completed successfully. |
|
q_xAborted |
BOOL |
If this output is set to TRUE, the function block execution has been aborted. |
|
q_xError |
BOOL |
If this output is set to TRUE, an error has been detected. For details, refer to q_etResult and q_etResultMsg. |
|
q_etResult |
ET_Result |
Provides diagnostic and status information as a numeric value. |
|
q_sResultMsg |
STRING [80] |
Provides additional diagnostic and status information as a text message. |