Binary File Writer

Write data to binary files

• 

Libraries:
DSP System Toolbox / Sinks

Description

The Binary File Writer block writes multichannel signal data to a binary file. The block specifies the name of the file and the structure of the header that precedes the signal data. If there is no header to write, the block specifies an empty structure, struct([]). The first time you write to the file, the block writes the header, followed by the data. On subsequent calls, the block writes the remaining data. If the header is empty, then no header is written.

The block writes the data in a row-major format. For example, if the input array is [1 2 4 5; 8 7 9 2], the block writes the data as [1 2 4 5 8 7 9 2].

Examples

Write and Read Binary Files in Simulink

Write data to a binary file and read the same data in Simulink^®.

• Open Script

Write and Read Matrix Data from Binary Files in Simulink

Write matrix data to a binary file. Read the data as a real matrix and a complex matrix.

• Open Script

Write and Read Fixed-Point Data from Binary Files in Simulink

Write and read fixed-point data from a binary file.

• Open Script

Write and Read Character Data from Binary Files in Simulink

Write and read character data from a binary file.

• Open Script

Ports

Input

Port_1 — Data to write

column vector | row vector | matrix

The writer block writes the data to the file specified in the File name parameter. If the File header structure is not empty, then the writer writes the header before writing the data. The block can write floating-point data and integer data. The input data can be real or complex. When the data is complex, the block writes the data as interleaved real and imaginary components. The writer assumes the default endianness of the host machine.

The input can be a variable-size signal, that is, you can change the frame size (number of rows) of the signal during simulation but the number of channels (columns) must remain constant. (since R2025a)

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64
Complex Number Support: Yes

Parameters

File name — Name of the file

'Untitled.bin' (default) | character vector

Name of the file to which the block writes the data.

File header — Size of the header

struct([]) (default) | structure

The structure can have an arbitrary number of fields. Each field of the structure must be a real matrix of a built-in type. For example, if File header is set to struct('field1',1:10,'field2',single(1)), the block writes a header formed by 10 double-precision values, (1:10), followed by 1 single precision value, single(1). If there is no header to write, set this parameter to an empty structure, struct([]).

Simulate using — Type of simulation to run

Interpreted execution (default) | Code generation

Specify the type of simulation to run. You can set this parameter to:

• Interpreted execution –– Simulate model using the MATLAB^® interpreter. This option shortens startup time.

• Code generation –– Simulate model using generated C code. The first time you run a simulation, Simulink generates C code for the block. The C code is reused for subsequent simulations as long as the model does not change. This option requires additional startup time but provides faster subsequent simulations.

Block Characteristics

Data Types	double | integer | single
Direct Feedthrough	no
Multidimensional Signals	no
Variable-Size Signals	yes
Zero-Crossing Detection	no

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Version History

Introduced in R2016b

R2025a: Support for variable-size signals

The Binary File Writer block supports variable-size input signals, that is, you can change the frame size (number of rows) of the signal during simulation but the number of channels (columns) must remain constant.

R2024a: Change in the default value of Simulate using parameter

The default value of the Simulate using parameter is now Interpreted execution. With this change, the block uses the MATLAB interpreter for simulation by default.