Documentation

FieldTalk Modbus Master C++ Library  Library version 2.13.3
MbusMasterFunctions::FileSubRequest Struct Reference

File subrequest structure. More...

Public Attributes

int refType
 Reference type (Must be specified as 6).
 
int fileNo
 File number (Range 1-65535). 3 is the input registers file, 4 is the holding registers file.
 
int recordNo
 Record Number (Range: 0 - 65535). The first record (aka register) to read from, 0-based numbering.
 
short * recordArr
 Pointer to a buffer which will be filled with the data read or contains the data to be sent.
 
int recordCnt
 Number of records (aka registers) this buffer holds (Range 1-125).
 

Detailed Description

File subrequest structure.

A Read or Write File Record function can can read multiple groups of references using subrequests. This struct defines such a subrequest.

Note
The quantity of records to be read, combined with all other fields in the in the expected response, must not exceed the allowable length of 253 bytes.