Renesas RX72N Envision Kit - Review

Table of contents

RoadTest: Renesas RX72N Envision Kit

Author: gordonmx

Creation date:

Evaluation Type: Development Boards & Tools

Did you receive all parts the manufacturer stated would be included in the package?: True

What other parts do you consider comparable to this product?: RX65N Envision Kit

What were the biggest problems encountered?: Poor documentation & Unstable firmware versions

Detailed Review:

NOTE: I tried to submit my review on 08/06, as per the review deadline, but the E14 website was not online.

 

First off, I would like to thank Renesas and Element 14 for the opportunity to evaluate the Renesas RX72N Envision Evaluation Kit (“the Kit or REK”). 

 

Summary Conclusion –

I have used Renesas dev/eval kits in the past, including most recently the RX65N Envision evaluation kit (REK) with mixed reviews, so the RX72N was a little more pleasant experience.  My evaluation went smoother than I had expected, but there is so much more than could have been demonstrated if more (or better) documentation and examples were available.  The datasheet claims the RX72N as its “flagship” MCU from the RX family and from the list of features packed into this 240 MHz single chip, although the board doesn’t run at anywhere near this speed.  Starting on a positive note, in the past, one issue I have had with Renesas and well as other vendors’ dev and eval boards is the absent of source and compiled copies of the preloaded demo programs.  During evaluating a board it is nice to be able to check that my IDE is setup correctly or to be able to return to a known state before trying something new.  The source and compiled demo code is a great way to verify this.  This time around Renesas supplied the GitHub repository for the demo code.  Since reviewing the RX65N, I was glad to see an improvement in the community forum.  During my evaluation I ran into 2 occasions where I submitted questions to the forum and received answers within an hour.  But I also had a very frustrating experience with a reply and another question.  As mentioned in the body of my review, although the performance I observed was impressive, fully loaded with a lot of potential and worthy of looking into further, the support in documentation was less than recommendable to all but the experienced programmer.  Another concern is the limited trial period (60 days) for the recommended CC-RX compiler. Sadly unless you have some experience with Renesas IDE, I would not like my boss to drop this off on my desk on Friday afternoon and ask to see a demo on Monday morning.

 

With all the issues with the RX72N Envision board, I was still impressed with the speed and overall performance of the board.  The integrated on-chip FPU, GPU and 2D drawing engine, as well as the reference design support circuitry for WiFi and audio is clearly an advantage in the RX72N REK.  I did not get a chance to measure the power consumption, but that is for another day. I have worked with other manufacturer’s touch screen displays and felt the smoothness and feel of the interface to be very comparable.  I would like to see the demo programs updated to incorporate multi-touch on the display, audio and WiFi examples.  I look forward to continuing exploring

 

Pros –

  • Powerful 32bit, 240MHz RX MCU,
  • On-chip double precision FPU,
  • On-chip WQVGA Graphic LCD Controller (GLCDC) with 2D drawing engine,
  • 4MB + 64KB ROM/ 1MB RAM – On-chip memory,
  • 4MB Serial Flash – On-board memory,
  • ESP32 WiFi/BLE interface module
  • 4.3” LCD touch screen with limited features,
  • Pmod interface (x2),
  • Free Eclipse-based IDE with GUI development plugin,
  • Free GCC (selective) and sized-limited CC-RX compilers support,
  • Free to use Segger emWin graphic library,
  • Open source hardware and software,
  • Easy to access myRenesas user community forum (renesasrulz.com).

 

Cons –

  • The “getting started” documentation was limited and seem to be more an app brief summary for interfacing with AWS.  It wasn’t completely bad, but required a little deeper knowledge of AWS before digging into the RX72N itself.
  • The introduction to the IDE in relation to the REK was vague.  Again not beginner friendly.
  • The source code is poorly documented.  I found firmware source code on the internet with no revision notes or date stamps.
  • Renesas CC-RX compiler (recommended) has only a 60 day trial period before you must buy a license. This is way too short of evaluation time given the complexity of the REK.
  • Some of the documentation (i.e. schematics) seems to be incomplete.
  • The kit is targeted to experienced Renesas programmers and not suited for beginners, even those familiar with Eclipse.

 

 

Wish List –

  • Add clearer instructions for compiling and installing the demo code, especially the secure bootloader firmware.
  • Add more code examples for board features (i.e. Audio, OTA, etc.)
  • Add the option to upload pictures and files to the user forum postings.
  • Add multi-touch capability demo to the touch screen.
  • Add a virtual extended workshop to help engineers come up to speed on the kit and IDE.  Renesas did this recently for EK-RA4M3 and it was very helpful in going up to speed.  Sign me up if you decide to have one!

 

LATE BREAKING NEWS ** LATE BREAKING NEWS ** LATE BREAKING NEWS

I finished my board testing a couple of weeks ago to write my review.  As I was finishing and reviewing my report I took a last look at the GitHub Wiki page to find that somebody has been busy working on some more coding examples.  As usual the examples would use some more documentation, but this is a good start. Thumbs up!

LATE BREAKING NEWS ** LATE BREAKING NEWS ** LATE BREAKING NEWS

 

Useful Document Links-

NOTE:  Logging in to the respective websites may be required to access some of the documents.

 

  • Renesas’ Getting Started With The RX72N Envision Kit User’s Guide (Software Manual/App Note):

        https://www.renesas.com/us/en/document/mas/getting-started-rx72n-envision-kit?language=en

   NOTE: This website contains links to the demo program source and binary files

  • RX72N Envision Kit Optimized for HMI Development in IoT Applications (Video):

    https://www.renesas.com/us/en/video/rx72n-envision-kit-optimized-hmi-development-iot-applications

    NOTE:  Good overview.  Also available through the Renesas’ RX72N-Envision-Kit Homepage

 

Renesas Software Tools -

  • GUI Development by Using QE for Display & emWin GUI (Video):

    https://www.renesas.com/us/en/products/microcontrollers-microprocessors/rx-32-bit-performance-efficiency-mcus/rx-gui-solutions

  • Renesas RX Family Amazon FreeRTOS download with E2 Studio (App Note): 

        https://www.renesas.com/us/en/document/apn/rx-family-amazon-freertos-download-e-studio

  • Renesas Flash Programmer v3.08.03 for Windows(Download):

    https://www.renesas.com/document/swe/renesas-flash-programmer-v30803-windows?language=en&r=488871

 

AWS/FreeRTOS -

NOTE:  The pdf is only 436 pages

 

 

Part I – What is the RX72N Envision Kit…

Before diving into my actual review of the Renesas RX72N Envision Evaluation Kit, P/N RTK5RX72N0C00000BJ, let’s take a look at what it is.  From what I can piece together from various documentation and websites, the kit itself is a fairly new higher end addition to the RX family.  The current hardware manual, rev 1.0, is date March 2020. Renesas has an intro video dated the same month. 

 

Since the kit is part of the larger RX family which has been around for a while, one would think that the design and support should be fairly stable, but it does beg the question about support life of the components used in the evaluation board.  As stated in the hardware user’s manual the purpose of the kit is as an evaluation tool for Renesas’ RX72N microcontroller.  In other words, although there is some limited value as a development board, its main purpose is to showcase the very useful features of the RX family and specifically the RX72N MCU.  One of the main targeted markets for the RX72N is the human machine interface (HMI) as shown through the main features of the integrated RX72N MCU:

 

  • Graphic LCD Controller (GLCDC/GPU) used to drive a 272 x 480 pixel WQVGA TFT display,
  • 2D Graphics Drawing Engine (DRW2D),
  • Single & Double-Precision 64-bit IEEE-754 Floating Point Unit (FPU),
  • Precision DSP functionality,
  • Dual bank flash memory for exchanging start-up program,
  • JTAG & FINE debugging interfaces
  • Secure bootloader (SW driven)
  • E2 Lite debugging (requires a USB port on the RX72N)
  • USB 2.0 Host

 

The kit also highlights addition on board features as it combines other manufacturer’s peripheral components such as:

 

  • QSPI Serial Flash (Macronix),
  • 480 x 272 pixel WQVGA TFT display with Touch Controller (RGB565/FT5206)
  • LCD Backlight (Intersil/Renesas),
  • Audio SoC (Intersil/Renesas),
  • MEMS Microphone (TDK)
  • ESP32 WiFi/BLE interface module
  • USB-to-Serial Interface (Renesas RL78),
  • E2-Lite Emulator (Renesas RX231 MCU) NOTE:  Interestingly the RX230 does not appear on any of the schematics
  • Micro SD card slot,
  • Ethernet port,
  • USB host port,
  • 2 Pmod ports

 

The preinstalled program is used to demonstrate some, but not all, these features.

 

From the user’s H/W manual, the following pictures show the general block diagram and component layout of the PCB.

RX72N Envision Evaluation Board Block Diagram

 

Board Layout – Component Side w/ Display Removed

Board Layout – Component Side w/ Display Installed

RX72N MCU Block Diagram (from datasheet)

 

The pre-installed firmware is partitioned into 3 intertwined segments. The first segment is the secure bootloader which is compiled and installed first using the unsecured program installer using either its Motorola S-Record (.mot) or .bin file.  The second segment is the “standard” program which includes 4 GUI-based sports games (Archery, 400m race, Weightlifting and Bicycle Race) to demonstrate the display and touch screen features.  The final segment is the “benchmark” program which includes the GUI-based secure update via the SD card slot, a serial terminal, network statistics and Amazon FreeRTOS log screen demos.  The last 2 segments are initially loaded as part of the full demo firmware install, but for the firmware swapping demo are converted to Renesas Secure (.rsu) files and loaded from the SD card as 3 separate files, Items 1,2 and 3.  This is where the 3 programs are intertwined.  When the bank swapping demo from the standard program is called it initiates the secure update window from the benchmark program which uses the secure bootloader to actually load the new firmware.  If you don’t have the standard program to call the benchmark program to call the bootloader the whole demo falls apart.  NOTE: Bear in mind if you don’t take care in using the secure firmware swapping feature of the board you can accidentally erase/overwrite the demo firmware.

 

Part II – The Unpacking: 

I have read many different views on the value and/or importance of the unpacking segment, but I feel it is important because it is often our first glimpse into what to expect in the product and support.  I was especially interested in their touchscreen technology.

The shipping box arrived undamaged, always a good sign, and well packed. Obviously, it wasn’t shipped by Amazon 8^).

The sole item in the box has the RX72N Envision evaluation board itself packaged in a very “retro” looking box.  No USB, or Ethernet cables were included, but who doesn’t have a box of spare cables lying around.  No documentation (i.e. quick start guide, etc.) was included except a web link shown on the back of the box.

 

Inside the retro package, the eval board was well protected in an anti-static bubble bag.  As a side note the board was manufactured Meistier Corporation in Kumamoto, Japan.

 

The “Kit’s” packaging –

The “Kit’s” Initial Instructional and Disclaimer Information –

   

The “Kit’s” Content, Front and Back –

   

The locations of the RX72N, SD card slot, PMOD connectors and ESP WiFi module

 

Part III – Initial Board Power On: 

At this time I normally power up the kit to get a feel for whether the unit will show any sign of life.  The good news is it did power up (i.e. no smoke or blank-screen-of-death).  The bad news is this is where things start to get a little blogged down (and so early in the review) mainly because of the lack of documentation.  As mentioned earlier the out-of-box board comes preprogrammed with the 3 software components (i.e. secure bootloader, graphics & benchmark programs).  After a short boot screen the board loads the graphics or games display demo program GUI (Bank 0).

   

Out-Of-Box Power-On Boot Screen                        Out-Of-Box – GUI Display Home Screen

NOTE:  Line 6 of the boot log shows “start bank = 0”

 

Using the embedded graphic GUI you can try out the touch screen and view the display response through playing 4 different games: Archery, 400m Race, Weightlifting and Bicycle Race. 

All the games are very similar in function and contains a help screen access through the (?) icon, a “SET NAME” input panel and a “HIGHSCORE” table all found on the GUI display home screen shown above. 

As mentioned above, all the games are similar in function and used to show the smooth display action of the GPU/FPU and the touchscreen.  For evaluation purposes a single game that demonstrated addition features such as the multi-touch feature of the controller or adding audio to the game(s) would have been more informative.  Once I was able to “lock up” the screen on one of the games by tapping the control icon very quickly.  NOTE: The board has no reset button. If you want to power cycle the REK you must disconnect the power either through the external power supply or by disconnecting the USB cable!!! 

 

As a side note, the RX65N envision kit display had screen buttons to disable/enable the GPU and/or FPU during operation to see the benefit of each unit. The RX72N kit does not.  Still the display motion and single touch/slide of the REK is pretty amazing.

 

The benchmark (BM) and secure bootloader programs are loaded on Bank 1 of the duel bootloader memory.  The operator must press SW2 3 times to initiate the swap to Bank1.

Benchmark (Memory Bank 1) Boot Screen        Benchmark Home Screen

NOTE:  Line 6 of the boot log shows “start bank = 1”

NOTE:  The current memory bank is retained during power cycling.

 

The first screen that appears after touching the benchmark home screen is the “Firmware Update via SD Card” display.  As you might guess, by inserting a SD card with a valid install file (i.e. .mot, etc.) you could download to the board a new program. Lucky for me Renesas supplied the compiled demo file (userprog.mot) at the GitHub site.  However, the file was not recognized by the board because .mot files are unsecure.  To load a program using the SD Card update screen you must first convert your .mot file to an .rsu file.  This can be done using the Renesas Secure Flash Programmer converter.

   

With userprog.mot (unsecured) file                      With userprog.rsu (secured) file

 

By touching [next] you navigate to the “Serial Terminal” screen:

Through a little trial and error the ports setting on Tera Term turn out to be shown above, but the communications seem to be only one way (PC to REK) at this time. The assumption is this may be used in conjunction with the AWS setup, but again there is no documentation to support this.

 

Which leads to another interesting feature of the REK, the serial connection to the board comes through the USB emulator port (CN8), whereas up to now we have been powering the REK through USB port, ECN1.  It turns out that the board’s power is only supplied through either the external power or ECN1 USB port.  This is confirmed by the schematic.

 

Finally, pressing [next] again brings you to the “Amazon FreeRTOS Log” screen which displays the progress of your connection to AWS.  The lower line of the LCD displays some of the current configuration states of the board, such as host USB and Ethernet IP address. With only the power supplied to the board the IP address is 0.0.0.0, but if you add an active Ethernet cable the REK will complete the initial connection and selftest.  Other that proof that you can complete a connection to AWS, I’m not sure what “DEMO FINISHED” really means, but again very little documentation hear.  NOTE:  To connect to AWS you must have a valid AWS account.

  No Ethernet connection                                          Active Ethernet connection

 

To return to the previous screen, touch [prev].  From the “Firmware Update …” display you can return to the GUI games (Bank 0) by pressing [Bank Swap] in the lower right hand corner/

 

 

Part IV - Updating the e2Studio IDE Software:

Before jumping into the installation process, I wanted to show you my PC information:

This is important because while was deciding on applying for the RoadTest I noticed that in the “Getting Started With The RX72N Envision Kit” app note (page 3) listed support for Windows 7, which is my preferred OS on my eval PC.  Since Windows 7 is no longer supported by Microsoft, many eval board manufacturers (i.e. SiLabs, Renesas, etc.} have moved to Windows 10 only for their newer IDEs. So until I take the time to build a newer eval PC, with all my favorite support tools, I’m excited for any vendor that supports my OS.

 

Under normal circumstances I would completely remove any installation of required software (i.e. IDE, compiler, etc.) and follow the available documentation to re-install and get a better feel whether the kit supplies enough instructions to start the customer on the right path.  So I decide to try the IDE’s software update feature instead.  My starting point was version 7.6.0

To check for updates, go to [Help] -> [Check for Updates] on the menu bar.  NOTE: During the process of checking for updates, there were no progress indicators and took a while to complete (~ 15 minutes on my PC).

 

The number of available update components was quite large, but I did [Select All].  After accepting a couple of licensing agreements, installing anyway despite the following security warning, code generator registration and restart, my current install is now version 7.8.0.

NOTE:  Remember the app note mentioned Windows 7 support.  The V7.8.0 E2 release notes and User’s manual lists OS requirement as Win 8.1 or greater, so we‘ll see.

 

Next after restarting E2 studio and choosing a workspace,

 

We’re ready to add some plug-ins by selecting [Help] -> [Install New Software…]

If not already installed, update to CC-RX v3.02.00

 

NOTE:  If you need to add a device family (i.e. RX, RA, etc.) during the update, you will need to run the offline installer to modify your IDE configuration.  One would think it could be included in the update process, but it is not.

When you setup your project you will want to select the Smart Configurator which uses your Board Specific Package (BSP) information file, sometime referred to as FIT modules, to simplify your process.

Installing QE for Display [RX] (QEfD-RX) Development Assistance Tool for Display

The QE for Display [RX] is a graphic development program that is tightly coupled to the RX GLCDC to simplify the LCD GUI layout and design.  As an interesting note, it seems that many of the software tools used for the eval and dev boards are currently being updated.  The latest IDE doesn’t support the RX family yet.  Included in the updates is a change from QE for Display to Aeropoint modules, although support for both tools is currently available. 

 

But back to the install.  Download the QEfD-RX, version 1.3.0 zip file, from the link shown in the Useful Document Links section for this review.  Following the instructions from application note R20AN0487EJ0110, rev 1.10, QE for Display [RX] Sample Program, open E2 studio and go to [Help] -> [Install New Software…], then click [Add…].  Enter your install file path into Location

Press [OK] -> [Next} ->[Next], review and accept QE license then press [Finish]

 

Finally to round out our installs we will import Amazon’s FreeRTOS (with IoT libraries) module, version 202002.00-rx-1.02, as recommended in the “Getting started …” app note.

 

Open E2 studio, click [File] -> [Import], select [General] -> Renesas GitHub Amazon FreeRTOS Project -> Next

Click [Check for more version…] for a menu of available versions.  NOTE:  Unfortunately, the recommended version is not available, so I choose the latest RX version (Fingers Crossed)

 

NOTE:  My biggest concern at this time is that despite the comment of support for Windows 7 in the “Getting Started…” app note, the other supporting components used by the examples may not.

 

Part V – Finally the Build…

To made a long story short (almost never my style) I loaded the project and pressed “Build All”

 

My license had expired!!!!  After all that work.  I contacted Renesas forum, but to no avail.  I believe it probably due to having updated my current install instead of run a fresh install.  I understand that Renesas supports GCC compilers in general, but it would be nice to have a GCC version of the examples.

 

Part VI – Conclusion

As mentioned earlier the goal in my review is to evaluate the out-of-the-box experience with Renesas RX72N Envision Evaluation Kit. Was the documentation complete? Were the items included or readily available enough to evaluate the advertised features?  Were code examples available?  Was support available?  Was support helpful?  My answer too many of these question would be marginable at best.

 

I’ve worked with Renesas dev kit in the past and was surprised and saddened with the current trend and issues I had with this one.  The enhanced features of the RX72N make it a worthwhile choice for graphic intensive portable products.  However, as mentioned in my summary conclusion at the beginning of this review, unless you have some experience with Renesas IDE, I would not like my boss to drop this off on my desk on Friday afternoon and ask to see a demo on Monday morning.  It feels like an engineer designed this board then gave it to a summer intern to document, then left for vacation.

 

The graphic interface impressive, but I would like to see more up-to-date samples and applications that highlighted more features like multi-touch, WiFi interface and OTA updating.  It was nice to have a fully load board, but let’s take advantage of those add components.

 

To beat a dead horse, the Eclipse-based e2 Studio is a very versatile IDE, but more time should be placed of verifying the demo source code and instructions.  I good example of the demo software code in the Segger source download file. 

 

There are a lot of details to digest in coming up to speed with the RX72N Envision kit that may be eliminated by a half-day virtual workshop like the one Renesas had for the EK-RA4M3.

 

What I didn’t try

Because I ran into so many problems early using my Windows 7 PC I did not get to explore all the little extras surrounding secure firmware swapping, but maybe in the future.

 

What’s next?

I would like to continue to troubleshoot these issues on my Windows 7 system.  I’m also looking for to running another evaluation using a Windows 10 PC, as well as dive a little deeper into the GUI building using Segger’s emWin libraries, as well as the dual memory bank swapping for firmware updating.  I will post updates as time permits.  My only issue is the limited remaining time on the compiler license, so I may have to port some of the source to GCC.

 

Please let me know if I missed something in the documentation.  Also please pardon my typos.

 

Gordon Margulieux

Twin Falls, ID USA

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