Texas Instruments C28 Series User Manual

Function Descriptions
3.2 Complex Fast Fourier Transform (Unaligned)
Description:
This module computes a 32-bit floating-point complex FFT including input bit reversing. This
version of the function does not have any buffer alignment requirements. If you can align the
input buffer, then use the CFFT_f32 function for improved performance
Header File:
FPU.h
Declaration:
void CFFT_f32u (CFFT_F32_STRUCT
*
)
Usage:
A pointer to the following structure is passed to the CFFT_f32 function.It is the same structure
described in the CFFT_f32 section:
typedef struct {
float32
*
InPtr;
float32
*
OutPtr;
float32
*
CoefPtr;
float32
*
CurrentInPtr;
float32
*
CurrentOutPtr;
Uint16 Stages;
Uint16 FFTSize;
} CFFT_F32_STRUCT;
Table 3.2 describes each element describes each element with the exception that the input
buffer does not require alignment.
Alignment Requirements:
None
Notes:
1. This function is not re-entrant as it uses global variables to store arguments; these
will be overwritten if the function is invoked while it is currently processing.
2. If you can align the input buffer to a 4*FFTSize, then consider using the CFFT_f32
function which has input buffer alignment requirements, but it is more cycle efficient
3. All buffers and stack are placed in internal memory (zero-wait states in data space).
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Texas Instruments C28 Series Specifications

General

Architecture	32-bit
Core	TMS320C28x
Operating Voltage	3.3 V
Operating Temperature	-40°C to 125°C
ADC	12-bit
Communication Interfaces	CAN, SPI, I2C, SCI
Peripherals	Timers
Package	Various (e.g., LQFP, BGA)

Summary

Introduction to C28x FPU Library

C28x FPU Library Structure

Library Build Options

Details the compiler options used to build the FPU library.

FPU Library Header Files

Explains the purpose and content of the library's header files.

C Functions and IQMath Integration

Discusses the use of C functions and IQMath in the FPU library.

C28x FPU Library Function Descriptions

DSP Routines Overview

Covers Fast Fourier Transforms (FFT) and related functions for signal processing.

Vector and Matrix Operations

Provides functions for element-wise operations on complex and real vectors.

Core Math Functions

Includes fundamental math operations like square root.

Optimized Utility Functions

Offers optimized memory copy and set operations.

FPU Library Revision History

Important Notice and Disclaimers