Datalog

Table of Contents

• Introduction
• Features Supported
• Features Not Supported
• Benchmark Results
• Provided Examples
• API

Introduction

The Datalog library module is commonly found in both digital control and motor-control applications. This module stores the real time values of user selectable variables. User configurable, "n" number of variables are selected by configuring "n" module inputs, iptr[0], iptr[1], ... iptr[n-1], pointing to the address of "n" variables. Data values are stored in datalog buffers, datalogBuff[0], datalogBuff[1], ... datalogBuff[n-1].

Number of datalog channels, buffer size and data type are configurable by user with "${SDK_INSTALL_PATH}/source/rtlibs/utilities/datalog/include/datalog_input.h" file update.

Features Supported

Datalog library module includes user configurable:

• Number of datalog channels (n)
• Datalog buffer size
• Data type to be stored
• Trigger type and trigger value
• Prescalar

Features Not Supported

N/A

Benchmark Results

A benchmark on Arm® Cortex®-R5F core has been conducted to observe the following results when running the following functions:

DATALOG Function	CPU Cycles
Auto Trigger
DATALOG_update	68
Manual Trigger
DATALOG_update	73

• Ran with TI Clang Compiler v3.2.1.LTS, with -Os flag and functions force-inlined onto the benchmarking function placed in TCM memory. Obtained the average result from 500 consecutive loops of running datalog functions with DPL CycleCountP, mimicking the usage of a control loop and overhead (~10 cycles) is removed.
• Actual result may vary depending on provided datasets and memory configuration. For Arm Cortex-R5F, it is recommended for users to map control loops to TCM for the best performance.

Provided Examples

The following examples have been provided to demonstrate datalog module:

• Datalog Test

API

APIs for Data Log Library

Note

Arm is a registered trademark of Arm Limited (or its subsidiaries or affiliates) in the US and/or elsewhere.