Analog Devices Implementing In-Place FFTs on SISD SIMD SHARC Processors Application Note

This document is a technical note on using ADSP-21065L and ADSP-21161 processors. It discusses the implementation of in-place FFTs and provides ASM code examples.

Brand: Analog Devices
Document type: Application Note
Language: English
Pages: 4
File format: PDF
File size: 33 KB
Published: 03 August, 2012
Updated: 30 September, 2023
Models: ADSP-21065L, ADSP-21161
MD5 checksum: 95B347E9BB3D7EB6A6C50AAD7FB4C09A
PDF: Analog Devices Implementing In-Place FFTs on SISD SIMD SHARC Processors Application Note PDF

About this manual

The document provides technical guidance for engineers on implementing in-place FFTs, which require no additional buffer memory, making them suitable for memory-constrained systems. It covers both SISD (ADSP-21065L) and SIMD (ADSP-21161) architectures.

What's inside

Introduction
DIT vs. DIF FFT Routines
Unscrambling the Results
Approach 1: Sequential Traversal
Approach 2: Decision Table
Approach 3: Look-up Table
Performance Analysis
Appendix Code List

Frequently asked questions

What is an in-place FFT?

An in-place FFT is calculated entirely inside its original sample memory, requiring no additional buffer memory.

Which SHARC processors are covered?

The note covers the ADSP-21065L (SISD) and ADSP-21161 (SIMD) processors.

Which FFT algorithm is used in the examples?

The provided example code uses a radix-2 DIF (decimation-in-frequency) FFT algorithm.

Download PDF (33 KB)