LEA Operation
448
SLAU367P – October 2012 – Revised April 2020
Copyright © 2012–2020, Texas Instruments Incorporated
Low-Energy Accelerator (LEA) for Signal Processing
The LEA supports a various of commands that are used to perform vector-based mathematical operations.
lists the command groups that are available.
Table 17-1. LEA Command Groups
Group
Purpose or Use
Group 1
Basic pointwise vector and matrix operations
Group 2
Basic vector MAC operations (windowing, scaling, general)
Group 3
MAC, pointwise FIR, correlation, convolution
Group 4
Basic minimum/maximum vector search operations on 16-bit data
Group 5
Generic minimum/maximum search operations on 32-bit data
Group 6
Generic minimum/maximum search operations on dual 16-bit data and complex
Group 7
Block based FIR, correlation, convolution
Group 8
Taylor functions and operations on pointwise vectors and matrices
Group 9
FFT and iFFT bank filtering (DIT type)
Group 10
Bit-reversed carry propagated presort for DIT-FFTs
Group 11
FFT post operation for real points
Group 12
Vector and matrix deinterleave and sort functions
Group A
Programming structure and rearrange functions
Group B
Special functions for math, matrix, and DSP
17.2.1 Use the LEA in Programs
How the LEA operates is briefly described in
. It is not necessary to understand how the LEA
works or the details of the LEA registers. The
Digital Signal Processing (DSP) Library for MSP
offers easy-to-use APIs that use the functions of the LEA and provide a high-level
environment to use the LEA in various applications. The DSP Library is a set of highly optimized API
functions to perform many common signal processing operations on fixed-point numbers for MSP430
microcontrollers. The APIs automatically enable and use the LEA module if the LEA is available in the
target device, and apply the optimal configurations to the LEA registers with the correct sequence. If the
LEA is not available, the CPU is selected to perform the operations.
The full LEA commands are supported by the DSP Library APIs, which are listed in the
,
Low-Energy Accelerator (LEA) Frequently Asked Questions (FAQ)
, and
Processing Capabilities of the Low-Energy Accelerator on MSP430™ MCUs
The following sequence of operations is an example of performing a vector-based algorithm using the
LEA, DMA, ADC, and SPI.
1. The CPU sets up the DMA controller, ADC, and SPI.
2. A DMA channel collects samples from the ADC converter at a defined sampling rate and transfers data
to the LEA memory.
3. After a block of data has been collected, the CPU enables one or a series of operations of the LEA
using the APIs in the
Digital Signal Processing (DSP) Library for MSP Microcontrollers
to perform the
required algorithm (for example, FIR, IIR, correlation, or FFT).
4. When the algorithm is complete, another DMA channel transfers the result of that algorithm to the SPI.
5. The SPI transfers the data to an external device.