This document outlines how to use file input/output (I/O) functions in LabVIEW. It discusses the uses of file I/O VIs, the division of the file I/O palette into high-level and low-level VIs, common file I/O formats like text and binary, and how to incorporate file I/O into a VI by selecting the appropriate functions and specifying a file path. Mastering these file I/O techniques allows LabVIEW programs to efficiently read and write data from files.

2. OUTLINE
Introduction
Uses of File I/0 VIs and functions
Division of File I/0 Vis Palettes
Types of File I/O VIs
File I/0 Formats
How to Incorporate File I/O into a VI
Conclusion

4. Uses of file I/O VIs and functions.

5. File I/O VIs are used to handle all aspects of file I/O,
which includes the following:
 Opening and closing files
 Reading from or writing to files including
spreadsheets
 Managing files (moving, renaming, or changing file
characteristics)
 Managing configuration files (creating, modifying,
and reading)
 Changing file characteristics

6. Write data to a text file: you can use the following
functions to write data to a file
(Functions>>Programming>>File I/O):
•Open/Create/Replace File
•Write to Text File
•Close File (release the memory)
The following codes write a “Hello” string to a file

7. Division of the File I/O palette

10.  The high-level VIs perform read or write operations
in addition to opening and closing the file.
 If an error occurs, the high-level VIs display a dialog
box that describes the error.
 You can choose to halt execution or to continue.
However, because high-level VIs encapsulate the
entire file operation into one VI, they are difficult to
customize to any use other than the one intended

11. 2) Low-Level and Advanced File I/O VIs and
Functions:
The low-level File I/O VIs and functions are located on
the middle row of the Functions>>All Functions>>File
I/O palette and the Advanced File I/O functions are
located on the Functions>>All Functions>>File
I/O>>Advanced File Functions palette to control each
file I/O operation individually.

13.  Use the principal low-level functions to create or
open a file,
 write data to or read data from the file, and close the
file.
 The low-level VIs and functions can handle most file
I/O needs..
 Use low-level VIs for more specific tasks.

14. 3) File I/O Express VIs:
The Express VIs on the File I/O palette include
the Read LabVIEW Measurement File Express VI
and the Write LabVIEW Measurement File Express
VI.

15. The LabVIEW measurement data file (.lvm) is a tab-delimited
text file you can open with a spreadsheet application or a text-
editing application. In addition to the data an Express
VI generates, the .lvm file includes information about the
data, such as the date and time the data was generated.

16. TYPES OF FILE I/O VIs

17. There are two types of file I/O Vis that exist which
include High Levels and Low Levels.
1) High Level: Performs common I/O operations all in
one VI (i.e. opens, reads, and closes file).
 These VIs can be accessed in the Functions Palette: •
Functions Palette → File I/O
 These VIs can perform operations from the following
data types:
a. Characters to and from text files
b. Lines from text files
c. Arrays of single-precision numerics to and from
spreadsheet text files

18. d. Arrays of single-precision numerics or signed 16-bit
integers to and from binary files High-level VIs
always need a file path input and if one is not
assigned, an error message will appear prompting for
the file path.
2) Low Levels: Performs only one I/O operation (i.e.
reads file)

19. FILE I/O FORMATS

20. File I/O formats depend on the type of files being
used .There are three (3) types of formats exist:
 text
 binary and
 data log.
Some basic guidelines for choosing a data type are:
i. Text files are the most common and should be used
if the data will be used in programs such as Word
and Excel.
ii. ii. Binary files are more efficient than text files
with respect to disk space and speed and should be
used if memory and speed is crucial.

21. iii. Datalog files are the best way to store data if the
data will only be accessed in LabVIEW and if the
data structure is complex.

22. How to incorporate file I/O’s into a VI.

23.  Access File I/O operations by:
 Functions Palette → All-Functions → File I/O
 In addition to the File I/O operations, the user will
need to identify the File Path so that the VI knows
where the file can be accessed. Insert a File Path
Control or Indicator by:
 Controls Palette → All-Controls → String & Path
→ File Path Control or File Path Indicator

25. CONCLUSION:
The presentation describes the uses of file I/O Vis,
division of file I/O palette, types as well as file I/O
formats and lastly how to incorporate file I/O`s into a
VI.

26. THANKS FOR LISTENING
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OF
PRESENTATION