LibFINS API Reference – finslib_parameter_area_write()

finslib_parameter_area_write( sys, area_code, data, start_word, num_words );


Parameter Type Description
sys struct fins_sys_tp * A pointer to a structure with the FINS context
area_code uint16_t The parameter area to which the data must be written
data const uint16_t * Pointer to the buffer containing the data to be written to the parameter area
start_word uint16_t Offset from the beginning of the parameter area where writing of this data must start
num_words size_t Number of words to be written to the parameter area

Return Value

Type Description
int A return value from the list FINS_RETVAL_... indicating the result of the query


The function finslib_parameter_area_write() writes a block of data to a parameter area of a remote PLC over FINS protocol. The area which must be written is provided as a parameter. Also the starting offset an number of words to write are parameters to the finslib_parameter_area_write() function.

Note that all areas except for the routing table must be written in their entirety.

The I/O registration table can only be written if the CPU is in program mode. When that area is written while the CPU is running or in monitor mode, finslib_parameter_area_write() will still return FINS_RETVAL_SUCCESS but nothing will be written to the area. It is the responsibility of the calling party to first ensure that the CPU is stopped before the I/O registration table is written.

The return value is either FINS_RETVAL_SUCCESS when the function succeeded, or one of the other FINS_RETVAL_ values if an eror occurs. In the latter case depending on the error message it is not sure if none, some or all of the data has been written to the PLC and additional processing and communication with the PLC may be necessary to know or set the correct state of the parameter area memory contents of the PLC.

See Also