Investigating ARM Cortex® M33 core with TrustZone® – Unboxing and Getting Started

Hi, I’m Mark from embeddedpro® in the United Kingdom and Erich’s allowed me to be a guest blogger here on mcuoneclipse. At many industry events, trade shows and conferences I’ve seen and given presentations about TrustZone®, but have not found tutorials or practical information online.

So I’m creating a 17 part video tutorial series (it will be published weekly here) investigating the ARM Cortex® M33 core with the TrustZone® security extension. Each week from now until the end-of-year holidays I will let you know what I’ve found out with a blog here, and a video blog on youtube. My friends at NXP have given me a LPC55S69-EVK board as the basis for my experiments:

LPC55S69-EVK (linked from

This is my first quick post showing the unboxing of the LPC55S69-EVK and the out-of-box experience.

The evaluation kit arrived in a production-ready attractive white, glossy carton with the familiar NXP branding. Both the carton and the PCB contain the part number LPC55S69-EVK and the legacy name LPCXpresso55S69. I’ve chosen to adopt the “EVK” name which is common to the RT10xx development kits (for example MIMXRT1064-EVK).

Once opened, the carton contains the evaluation kit in an anti-static bag, a one-page flier showing the major components of the board and the jumper settings, and lastly a small bag of 0.1″ pitch headers (not photographed). The headers can be used to configure the evaluation kit, but these were not necessary for my first use of the board. I was in such a hurry to get my hands on the board that I opened the bag before taking this photograph:

The evaluation kit provides an extensive list of features. Simply looking at the board I can see audio support (both output and line input via 3.5mm stereo jack plugs supported by Cirrus Logic WM8904), Arduino (it appears to be mechanically compatible with UNO R3 shield boards), MikroElectronika Click mikrobus headers, some user buttons and a tri-colour LED, a PMOD host connector, and inbuilt CMSIS-DAP debugger, usb full speed and high speed connectors and a micro-SD socket (labelled SDIO – will this support WIFI SDIO cards as well as SD memory cards wonder??). As with many NXP development kits, there is a tiny accelerometer. I had to look at the board user guide to identify that this is a MMA8652FCR1.

Let’s take a look in more detail at the CMSIS-DAP debug chip:

We can see that SWD debugging on the LPC55S69-EVK is supported by LPC4322JET100 microcontroller. This is programmed with LPC-Link2 debugging firmware, and this will provide a great, fast debug connection (and as we will see in Week 9: low-cost, dual-core debugging capability).

So that’s it, my first “eyes-on” with LPC55S69-EVK. In the video I show the inbuilt example project, which includes an audio loop-back demo. This takes an audio input via the 3.5mm line-in socket, samples it with the audio codec WM8904, and outputs it back through the codec and onto the headphone socket. In the video I play some audio from my phone, via the LPC55S69 and out to an external speaker. It is here.

Come back next week and I’ll post my second video, Setting up your environment and creating your first project with MCUXpresso IDE for LPC55S69. And feel free to post a comment below to let me know of any features on the board that I missed.

What do you think?

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