Modules
FFTC LLD Data Structures & APIs

Modules

 FFTC LLD Symbols Defined
 FFTC LLD Data Structures
 FFTC LLD Functions

Detailed Description

Introduction

Overview

The FFT Coprocessor (FFTC) is an accelerator that can be used to perform FFT and IFFT on data. Using the FFTC to perform computations that otherwise would have been done in software frees up CPU cycles for other tasks. The FFTC module has been designed to be compatible with various OFDM based wireless standards like WiMax and LTE.

The FFTC hardware provides the following features:

  1. IFFT and FFT.
  2. Sizes
    1. 2^a * 3^b for 2 >= a >= 13, 0 >= b >= 1 - maximum 8192.
    2. 12 * 2^a * 3^b * 5^c for sizes between 12 and 1296.
  3. LTE 7.5KHz frequency shift.
  4. 16 bits I / 16 bits Q input and output.
  5. 444 Msubcarriers/sec throughput.
  6. 77 dB SNR.
  7. Dynamic and Programmable Scaling modes.
  8. Dynamic scaling mode returns block exponent.
  9. Support for "FFT Shift" (switch left/right halves)
  10. Support for cyclic prefix (addition/removal)
  11. Ping/Pong input, output buffers.
  12. Input data scaling with shift.
  13. Output data scaling.

This section of the documentation covers the FFTC Low Level Driver (LLD) APIs that include FFTC MMR access APIs and some utility APIs for formatting control headers and compiling FFT configuration for the hardware.

References

  1. FFTC User Guide

Copyright 2014, Texas Instruments Incorporated