Hiroyuki Nakaki
Hiroyuki Nakaki
Published: March 9, 2022

Due to the collaboration between the cloud and device vendors, we have set up the environment for implementing firmware updates of the MCU OTA (Over-The-Air) by using the cloud service.
[AWS certified program] OTA firmware update using AWS

This is a solution that can realize firmware updates of an MCU directly via an internet connection to the cloud services such as Amazon Web Services (AWS).

Actually, there are many cases where an embedded system comprises not only an MCU directly connected to the internet but also other MCUs (2nd  MCUs), aren’t they?

1st MCU & 2nd MCUs

For these systems, firmware updates of the 2nd MCUs are also important for continuous improvement of the service and mitigation of security risks.

With this understanding, the Renesas cloud connectivity solution development team has started providing the sample code to perform OTA firmware updates of the 2nd MCUs using the AWS IoT service that have no direct connection to the internet. You can download it from the below link.

  • Secondary device OTA update Demonstration Video 

Secondary Device OTA Update using FreeRTOS and Amazon Web Services | Renesas

 The 2nd MCUs using the AWS IoT
  • Application Note (Sample Code) R01AN6220:

RX65N Group Sample Code for OTA Update of Secondary Device with Amazon Web Services Using FreeRTOS | Renesas

Application Note (Sample Code) R01AN6220

In this demo, you can add an additional type of measurable sensors by implementing the sensor measurement function on the 2nd MCUs with Quick-Connect IoT and perform an OTA firmware update of the 2nd MCU via the AWS IoT service.

I will give you a short description of the OTA process using the AWS cloud.
The OTA process executed on an MCU with a direct connection to AWS is capable of controlling its own (1st MCU) hardware via the Platform Abstraction Layer (PAL) for OTA provided by AWS (See the figure left below.)
In addition to the PAL for its own (1st MCU) OTA, the 2nd MCU OTA can be realized by using the same method and preparing another PAL for communication with the 2nd MCU and transmission of OTA instructions.

OTA process using the AWS cloud

In addition to our unique approach, Renesas has provided a driver (FWUP FIT module) that can perform an OTA update on the 2nd MCU to reduce the load of the OTA implementation. 
The demo of the above URL can be realized by extending the FWUP FIT module. 
Similar to the other drivers, this driver is available at no cost.
Introducing the RX Family Firmware Update Middleware that can easily realize FOTA (Firmware Update Over-The-Air) implementation

You can switch the PAL for its own (1st MCU) OTA and 2nd MCU OTA by setting a parameter for issuing instructions for the OTA process on the AWS.

We will keep providing solutions that can make IoT development easier. Please stay tuned!

We have prepared a web page with a summary of cloud solutions for the RX family at the below link. You can see many useful solutions here, so please visit RX Cloud Connectivity Solution

There are also many blogs written on the cloud solution previously:

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