Application Note

R20AN0650EJ0101 Rev.1.01 Page 1 of 21

Dec.01.21

RL78/G23

Connecting to Amazon Web Services Using FreeRTOS

with RL78/G23-128p Fast Prototyping Board

Introduction

Amazon FreeRTOS is a real-time operating system that augments the FreeRTOS kernel with libraries for

connectivity, security, and over-the-air (OTA) updates. Amazon FreeRTOS also includes some demo

applications that demonstrate Amazon FreeRTOS features on qualified boards.

Renesas e

studio is a development environment based on the popular Eclipse CDT (C/C++ Development

Tooling), covers build (editor, compiler, and linker control) as well as debug interface. It also supports to

integrate the Amazon FreeRTOS demo applications and run them on Renesas boards.

This document describes a system combining the Renesas board RL78/G23-128p Fast Prototyping Board

and a Wi-Fi module (SX-ULPGN (from Silex Technology)). This system implements Amazon FreeRTOS in

the RL78/G23-128p to enable communication with Amazon Web Services (AWS) using the MQTT protocol

via Wi-Fi.

In addition, the general-purpose API for TCP/IP is provided in Amazon FreeRTOS. Communication with a

general-purpose Wi-Fi is also facilitated by using this API.

Objectives

This document helps users to be familiar with the procedures to run the Amazon FreeRTOS demo

applications using e

studio (from downloading the Renesas GitHub Amazon FreeRTOS projects to running

the demos).

Operating Environment

Operation was confirmed in the following environments.

IDE

studio 2021-07 (21.07.0)

https://www.renesas.com/software-tool/e-studio

Board

RL78/G23-128p Fast Prototyping Board

https://www.renesas.com/rl78g23-128p_fpb

Wi-Fi Pmod Expansion Board

https://www.renesas.com/products/microcontrollers-microprocessors/ra-

cortex-m-mcus/wi-fi-pmod-expansion-board-80211bgn-24g-wi-fi-pmod-

expansion-board

Toolchains

CCRL Compiler v1.10.00

https://www.renesas.com/products/software-tools/tools/compiler-

assembler/compiler-package-for-rl78-family.html

Emulators

E2 Emulator Lite

https://www.renesas.com/products/software-tools/tools/emulator/e2-emulator-

lite.html

RL78/G23 Connecting to Amazon Web Services Using FreeRTOS with RL78/G23-128p

Fast Prototyping Board

R20AN0650EJ0101 Rev.1.01 Page 2 of 21

Dec.01.21

Contents

1. Outline ..................................................................................................................................... 3

2. Preparing Amazon FreeRTOS projects .................................................................................... 3

2.1 Downloading FreeRTOS and importing demo ........................................................................................ 3

3. Preparing AWS ........................................................................................................................ 5

4. Preparing the hardware ........................................................................................................... 6

4.1 RL78/G23-128p Fast Prototyping Board ................................................................................................. 6

4.2 SX-ULPGN .............................................................................................................................................. 6

4.3 DIGILENT Pmod usbuart ........................................................................................................................ 7

4.4 Writing the certificate ............................................................................................................................... 7

4.4.1 Downloading SharkSSL ........................................................................................................................ 7

4.4.2 Obtaining the certificate data ................................................................................................................. 7

4.4.3 Obtaining the CA list (Class 2 Root CA) ............................................................................................... 8

4.4.4 Converting the certificate and private key to SharkSSL binary format ................................................ 11

4.4.5 Converting the CA list to SharkSSLPerseCAList binary format .......................................................... 11

4.4.6 Writing the certificate to SX-ULPGN ................................................................................................... 11

4.4.7 Connecting the SX-ULPGN ................................................................................................................. 14

4.5 Preparing to receive the debug log ....................................................................................................... 15

5. Building and running .............................................................................................................. 16

6. Demo operations confirm in AWS IoT console ....................................................................... 18

7. Appendix ............................................................................................................................... 19

7.1 How to upgrade drivers ......................................................................................................................... 19

Revision History ............................................................................................................................ 21

Note:

• AWS™ is a trademark of Amazon Web Services, Inc. (https://aws.amazon.com/trademark-guidelines/)

• FreeRTOS™ is a trademark of Amazon Web Services, Inc. (https://freertos.org/copyright.html)

• GitHub

is a trademark of GitHub, Inc. (https://github.com/logos)