FB_ReadCouplerRegs
This function block provides read access to the table register in the coupler and the registers of the intelligent terminals. The coupler itself is referred to as terminal 0 (null). All the other terminals in the terminal block, with the exception of passive terminals (such as power feed terminals), are counted in ascending sequence (beginning with 1). It is possible either to read all registers, or only a partial region (between nStartReg and nEndReg). Several seconds are required in order to read all the registers (0...255) in a table. Register values that have been successfully read are found in the structure stCouplerTable.The structure is an array of high and low bytes. Each array element corresponds to a register value (e.g.: stCouplerTable[ 5 ] == Register 5 ).
VAR_INPUT
VAR_INPUT
stState : PLCINTFSTRUCT;
nTerminal : BYTE := TERM_COUPLER;
nTable : BYTE;
nStartReg : BYTE;
nEndReg : BYTE;
bExecute : BOOL;
tTimeout : TIME;
END_VAR
stState : Status word of the 2-byte PLC interface. (PLCINTFSTRUCT)
nTerminal : Terminal number, to whose table register access is to be made. The coupler has terminal number null. Passive terminals are not to be counted.
nTable : Table number whose register values are to be read. Intelligent terminals only have one table for each terminal channel. A 4-channel terminal has the following table numbers: 0-3. An intelligent terminal, however, only possesses a maximum of 64 register values for each terminal channel.
nStartReg : The number of the first register that is to be read.
nEndReg : The number of the last register that is to be read.
bExecute: The function block is activated by a positive edge at this input.
tTimeout: States the length of the timeout that may not be exceeded during execution of the function.
VAR_OUTPUT
VAR_OUTPUT
stCtrl : PLCINTFSTRUCT;
bBusy : BOOL;
bError : BOOL;
nErrId : UDINT;
stCouplerTable: ST_CouplerTable;
END_VAR
stCtrl : Control word of the 2-byte PLC interface. (PLCINTFSTRUCT)
bBusy: This output is set when the block is activated, and remains set until execution of the function has been completed.
bError: If an error should occur during the execution of the function, then this output is set, after the bBusy output has been reset.
nErrId : Supplies the error number when the bError output is set.
Error number | Error description |
|---|---|
0 | No error |
0x100 | Error at initialisation of the communication via the 2 byte PLC interface |
0x200 | Error during communication |
0x300 | Timeout-Error. The permitted execution time was exceeded |
0x400 | Wrong parameter value at register number |
0x500 | Wrong parameter value at table number |
stCouplerTable : Structure containing the register values of the terminal or coupler that have been read (type: ST_CouplerTable).
Requirements
|
Development environment |
Target system type |
PLC libraries to include (category group) |
|---|---|---|
|
TwinCAT v3.1.0 |
PC or CX (x86, x64, ARM) |
Tc2_Coupler (IO) |