Hardware Reset for ARM Cortex-M with Segger J-Link and Kinetis Design Studio

The reset and signal line of a microcontroller is probably the most important signal to a microcontroller. And if things go wrong, then a first thing to check is the reset line. So having control over reset is an important aspect for embedded development. You would think that if you download a program to a microcontroller, the debug probe would put the device into reset at the start with a short pulse like this:

Reset Signal in Logic Analyzer

Reset Signal in Logic Analyzer

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3D Printed Classic Mac Apple Watch Charging Station

One of the first machine I used for development many years ago was a Apple Classic Macintosh computer. My days of development with Pascal and Modula-2 are long gone. But with the availability of 3D printers I can print a Classic Mac :-). But now it is not used for development: I use it to charge an Apple Watch:

3D Printed Apple Watch Charging Station

3D Printed Apple Watch Charging Station

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Renaming Eclipse CDT Projects

When I create a project in Eclipse (e.g. in Kinetis Design Studio with the GNU ARM Eclipse plugins), I have to specify the name of the project during creation time:

Project Name in Eclipse

Project Name in Eclipse

But what if I change my mind later on and want to use a different name? How to rename the project?

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USB CDC with the Raspberry Pi

For my home automation project with openHAB I want to attach Freescale (now NXP) FRDM (Freedom) boards so they can take care about the realtime aspects and to act as gateways to my other systems. One way is to use USB CDC (Serial over USB) as communication channel. USB has the advantage that it powers the board, plus I can attach multiple devices: up to four on the Raspberry Pi 2 and even more with using a USB hub. In a standard configuration with a USB WiFi and a USB HID (mouse plus keyboard) dongle I still can attach two Freescale (ahem, NXP) Freedom boards to the Raspberry Pi:

FRDM-K22F and FRDM-K64F attached to Raspberry Pi 2

FRDM-K22F and FRDM-K64F attached to Raspberry Pi 2

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Blinky LED with openHAB on Raspberry Pi

In my earlier post I showed how I have installed the open source openHAB home automation system (see “Installing openHAB Home Automation on Raspberry Pi“). In this post I show how to control a local LED on the Raspberry Pi with openHAB home automation system: how to control any GPIO pin on the Raspberry Pi from remote:

Controlling the LED with openHAB

Controlling the LED with openHAB

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Installing openHAB Home Automation on Raspberry Pi

I’m currently building a home automation project around Raspberry Pi: I want to be able to monitor and control things like the lights, garage doors and the heating system both at home and from remote. I already have added a touch screen to one of my Raspberry Pi 2 computers (see “Adding a Touch LCD to the Raspberry Pi 2“). This article is about how to install the openHAB on that Raspberry so it can be the brain of the automation system.

openHAB Demo House on Pi

openHAB Demo House on Pi

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