Isolated USB-to-UART converter


Jacob Beningo shows how to build an isolated USB to UART converter using Sparkfun’s modules.

A simple isolation circuit that costs only a few dollars could have been used to protect the USB port on the computer. Embedded system developers get used to plugging strange hardware and components into their computers on a daily basis and rarely consider the consequences of what their actions might bring.

Isolated USB-to-UART converter – [Link]

Inside the ALU of the first ARM microprocessor


Dave @ takes a look inside the first ARM microprocessor and explains it’s design.

With that in mind I embarked on my own attempt to reverse-engineer parts of the armv1. Some background knowledge of the processor’s architecture is helpful, and googling for “ARM Architecture Reference Manual” will lead you to very detailed descriptions of the more modern versions of the processor. By just looking at the masks and knowing a little about the processor’s architecture it’s possible to make some good guesses at what some of the blocks are.

Inside the ALU of the first ARM microprocessor – [Link]

INA219 current sensor DIY Breakout board


Juan Ignacio has designed a INA219 current sensor DIY Breakout board:

Another small board, this time for a INA219. The INA219 is a high-side current shunt and power monitor with an I2C interface.
For testing I used Rei VILO library with a MSP430G2553 and Energia, and I measured the power consumption for this simple circuit.

INA219 current sensor DIY Breakout board – [Link]

UCload new PCB build


Sjaak has published a new PCB build, uC controlled dummy load:

With no snow outside I finally got around to solder the 3rd PCB. It is the second revision of a microcontroller dummy load. It is loosely based on the arachnidlabs uc:load. It uses the same base ciruit and adds a microcontroller (PIC16F1825), rotary encode switch, external powersupply and offcourse a 128×32 OLED.

UCload new PCB build – [Link]

Adding a USB power port to a switch for IoT


Jesus Echavarria @ has tipped us with his latest project. In this project he adds a USB power port to a switch.

Also I need a power supply for the Arduino board, and I think that, better than a external USB AC wall adaptor or power supply, is modify the switch to add it a USB power port that can power the Arduino board. I’ve got at home a TP-Link TL-SF1008D, a simple 8 port 10/100 Mbps switch. So, let’s go to open it and add it the USB port!

Adding a USB power port to a switch for IoT – [Link]

Converting from Eagle to KiCad


lachlanA @ has published a Eagle SCH/LIB to KiCad SCH/LIB ULP conversion script:

The following 5 ulp (eagle user script file) and one ulp include file, work together or stand alone to convert Eagle sch/pcb version 6.xx(7.xx maybe?) file(s) and any version of Eagle lib(lbr) to KiCad sch/pcb and lib/mod files.

Converting from Eagle to KiCad – [Link]

ATtiny OLED Watch Core


陳亮 @ shows us his ATtiny85 OLED display build on a breadboard:

This instructable show how to use an ATtiny85 to create a tiny watch core that can run over 1 year before recharge or replace battery.

The instruction to make the watch case may be in next instructable.

I have made a few Arduino watch before, but I found the watch using ATmega boards or ATmega chips are a little bit too big to wear. So I would like to make it with a smaller chips.

ATtiny OLED Watch Core – [Link]

Setting Up Python web server for Raspberry Pi


Sankar Cheppali will show us how to setup a python based web server to serve simple html pages to the clients using Raspberry Pi.

Serving web pages from embedded devices is not easy task as embedded devices have limitations in processing power , memory available etc. But with Raspberry Pi this task becomes very easy. We have lot of packages, programming platforms and libraries to chose from because pi is from Linux family.

Setting Up Python web server for Raspberry Pi – [Link]

Raspberry Pi Zero 4 Port USB Hub


Peter van der Walt has designed a nice USB Hub for Raspberry Pi Zero computer. Design files are available on github:

In line with my other projects I need to make a USB hub attachment for the Pi Zero.
Seeing as the community figured out that the Raspberry Pi Design team was clever enough to leave us D+ and D- test points at the bottom, I came up with this design above.

Raspberry Pi Zero 4 Port USB Hub – [Link]