Data Mapper

Map integer symbols from one coding scheme to another

• Library:

• Communications Toolbox / Utility Blocks

• 

Description

The Data Mapper block accepts integer inputs and maps them to integer outputs. The mapping types include: binary to Gray coded, Gray coded to binary, and user defined. Additionally, a pass through option is available.

Gray coding is an ordering of binary numbers such that all adjacent numbers differ by only one bit.

Ports

Input

Port_1 — Input port

scalar | column vector | matrix

Input signal, specified as a scalar, vector, or matrix of integers. Elements of the input signal must be nonnegative values. The block truncates noninteger values to integer values. When the input is a matrix, the columns are treated as independent channels.

Data Types: double | single | int8 | int16 | int32 | uint8 | uint16 | uint32

Output

Port_2 — Output signal

scalar | column vector | matrix

Output signal, returned as a scalar, column vector, or matrix. The dimensions of the output signal match those of the input signal.

Data Types: double | single | int8 | int16 | int32 | uint8 | uint16 | uint32

Parameters

Mapping mode — Mapping mode

Binary to Gray (default) | Gray to Binary | User Defined | Straight through

Mapping mode, specified as one of the four options. The mapping for the Binary to Gray and the Gray to Binary modes are shown in the following table when the inputs range from 0 to 7.

Binary to Gray Mode		Gray to Binary Mode
Input	Output	Input	Output
0	0 (000)	0 (000)	0
1	1 (001)	1 (001)	1
2	3 (011)	2 (010)	3
3	2 (010)	3 (011)	2
4	6 (110)	4 (100)	7
5	7 (111)	5 (101)	6
6	5 (101)	6 (110)	4
7	4 (100)	7 (111)	5

When you select the User Defined mode, you can use any arbitrary mapping by providing a vector to specify the output ordering. When you select the Straight Through mode, the output equals the input.

Symbol set size (M) — Symbol set size

8 (default) | positive integer

Symbol set size, specified as a positive integer. This parameter restricts the inputs and outputs to integers in the range of 0 to M-1.

Mapping vector — Maps input elements to the output elements

[0 1 3 2 7 6 4 5] (default) | vector

Mapping vector, specified as vector of nonnegative integers whose length equals . This parameter defines the relationship between the input and output integers. For example, the vector [1 5 0 4 2 3] defines the following mapping:

$$\begin{array}{l}0\to 1\hfill \\ 1\to 5\hfill \\ 2\to 0\hfill \\ 3\to 4\hfill \\ 4\to 2\hfill \\ 5\to 3\hfill \end{array}$$

Model Examples

Binary to Gray Conversion in Simulink

Use the Open model button to open the Binary-to-Gray model. The model converts a binary sequence to a Gray-coded sequence and vice versa by using Data Mapper blocks.

Block Characteristics

Data Types	double | fixed point | integer | single
Multidimensional Signals	no
Variable-Size Signals	no

Extended Capabilities

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