New NXP MCUXpresso Eclipse IDE v11.0

A few days ago NXP has released a new version of their Eclipse IDE flagship: the MCUXpresso IDE v11.0.

NXP MCUXpresso IDE V11.0.0

NXP MCUXpresso IDE V11.0.0

The previous v10.3.1 was released back in Feb 2019, and the 11.0 now in June this year matches up with the Fall university semester. I appreciate that the releases are about every 6 months, so this gives me time to use it in my university lecture material and lab work. I had the weekend for trying it out, and I’m very pleased.

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SWO with NXP i.MX RT1064-EVK Board

With the cost of an single pin, many ARM Cortex-M boards including the NXP i.MX RT1064 can produde SWO data: think about a pin able to stream data out of the chip in realtime. For example interrupt activity which otherwise might be hard to capture:

SWO Interrupt Trace

SWO Interrupt Trace

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Reverse Engineering of a Not-so-Secure IoT Device

The ‘Internet of Things’ is coming! It started as an overused marketing hype with no real use case (who needs internet connected fridges? Who wants the internet connected toilet paper?).

New ‘things’ start to pop up, useful or not: From smart bulbs (Philips Hue), thermostats (Nest), smart TV (Samsung and others) up to voice assistants (Alexa, Cortana, Google). You might even have installed one of these, right? What about temperature and humidity sensors? Probably there is nothing wrong with that?

But what would you think if one morning you find a strange unknown device installed under your working desk, connected to the cloud and internet?

IoT Device attached under a working desk
IoT Device attached under a working desk
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MCUXpresso Eclipse IDE Mouse Tips & Tricks

In a modern development workflow both command-line and a graphical user interface has its place. On the GUI side, Eclipse is famous that it offers many different ways to accomplish something which is great. But sometimes I continue to use an old habit or way because I have missed that there is a newer and better way, and the MCUXpresso Eclipse IDE is no exception to that. In this article I show a few ways how to use the mouse even more productive.

Project Settings

Project Settings

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Internal and External Debug Options for the NXP LPC55S69-EVK Board

The LPC55S69-EVK board comes on-board debug probe. The board includes the LPC4322JET100 device which acts like NXP LPC-Link2 debug probe:

LPC4322JET100 on LPC55S69-EVK

LPC4322JET100 on LPC55S69-EVK

But it is easily possible to use the board with an external debug probe or re-program the onboard one as a SEGGER J-Link debug probe.

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Building a Raspberry Pi UPS and Serial Login Console with tinyK22 (NXP K22FN512)

There are different ways to ruin a Linux system. For the Raspberry Pi which uses a micro SD card as the storage device by default, it comes with two challenges:

  1. Excessive writes to the SD card can wear it out
  2. Sudden power failure during a SD card write can corrupt the file system

For problem one I do I have a mitigation strategy (see “Log2Ram: Extending SD Card Lifetime for Raspberry Pi LoRaWAN Gateway“). Problem two can occur by user error (“you shall not turn it off without a sudo poweroff!”) or with the event of a power outage or black out. So for that problem I wanted to build a UPS for the Raspberry Pi.

Raspberry Pi with UPS System and tinyK22

Raspberry Pi with UPS System and tinyK22

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TrustZone with ARMv8-M and the NXP LPC55S69-EVK

The ARM TrustZone is an optional security feature for Cortex-M33 which shall improve the security for embedded applications running on microcontroller as the NXP LPC55S69 (dual-core M33) on the LPC55S69-EVK.

NXP LPC55S69-EVK Board

NXP LPC55S69-EVK Board

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First Steps with the LPC55S69-EVK (Dual-Core ARM Cortex-M33 with Trustzone)

For the long Easter weekend I have organized a new toy: the NXP LPC55S69-EVK board: a dual ARM Cortex-M33 running at 100 MHz with ARM TrustZone:

LPC55S69 Microcontroller

LPC55S69 Microcontroller

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Tutorial: MCUXpresso SDK with Linux, Part 2: Commandline Debugging with GDB

In “Tutorial: MCUXpresso SDK with Linux, Part 1: Installation and Build with Maked” I used cmake and make to build the SDK application. In this part I’m going to use the command line gdb to debug the application on the board.

Cross-Debugging with GDB

Cross-Debugging with GDB

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Be aware: Floating Point Operations on ARM Cortex-M4F

My mantra is *not* to use any floating point data types in embedded applications, or at least to avoid them whenever possible: for most applications they are not necessary and can be replaced by fixed point operations. Not only floating point operations have numerical problems, they can lead to performance problems as in the following (simplified) example:

#define NOF  64
static uint32_t samples[NOF];
static float Fsamples[NOF];
float fZeroCurrent = 8.0;

static void ProcessSamples(void) {
int i;

for (i=0; i < NOF; i++) {
Fsamples[i] = samples[i]*3.3/4096.0 - fZeroCurrent;
}
}
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