A development board for the STM32F042


Andy Brown designed a development board for the STM32F042 in the TSSOP20 package:

This project came about because I’m using the STM32F042F6P6 (32Kb flash, 6Kb SRAM) in another project where I’m creating a USB device and the first thing I did is try to obtain a development board for it. I was hopeful that ST would have created one of their ‘discovery’ boards but no, there was only a ‘nucleo’ board available and that had one of the QFP packages on it.

A development board for the STM32F042 – [Link]

Create a WordPress Site on Raspberry Pi


This tutorial guides you on how to install Apache server, MySQL and PHP in Raspberry Pi and then hosts a WordPress site on this. raspberrypituts.com writes:

This tutorial is using the Raspian Wheezy OS, Jesse has a similar installation but will not be the exact same. This is an easy tutorial on how to create a WordPress Site on Raspberry Pi. Comments? Questions? Post below!

Create a WordPress Site on Raspberry Pi – [Link]

Search Github projects by component – find design references


dangerousprototypes.com has launched a new search feature that is able to search GitHub for specific parts and enables you to easily find reference designs for your next projects. This new search feature can also display Schematics and PCB previews without having to open a CAD software on your local machine, but some limitations exists. They write:

TomKeddie first mentioned this idea at Hacker Camp Shenzhen, and later in the forum and on WeChat. Tom generously shared his scraping/search method. Eagle 6+ files are XML, so we can find them on Github by searching for the “eagle SYSTEM” tag in files with “extension:sch”. That gives more than the maximum 100 pages of results, so we filter by file size and increment size 500 bytes at a time “size:1001…1500″. We use the normal user search interface, parse the HTML results, and grab all urls ending with .sch. While Github has an API, that API doesn’t give access to search code search without specifying a repository by name (probably so people don’t do what we did…).

Search Github projects by component – find design references – [Link]

Arduino Weather Station (AWS)


by AdrieSentosa @ instructables.com:

In this project, we will be making a weather station that measures air pressure, temperature, rain drop, soil humidity and air humidity using Arduino which save the data for data acquisition!

Arduino Weather Station (AWS) – [Link]

Control Loop Challenges of Wireless Systems


Automation is defined as using various control systems to operate equipment such that there is minimal human intervention. Closed control loops (feedback systems) regulate how other systems or devices behave by taking into consideration their output and making corrections based on feedback. An example of this feedback system is Progressive Automation Linear Actuators. In this article challenges of control loops in wireless systems are discussed.

Though embedded modules can be used be used with Wi-Fi, the aim of recent protocols is providing wireless networks with more focused support for control loops. For tight control loops, devices supporting the IEEE802.15.4 ZigBee standard can be used in supporting the recent protocols. Below is a Microchip’s MRF24WB Wi-Fi module.

For sharing a common medium of communication, sensors and controllers are required by a control system that is adopting wireless communication. The network’s quality is a trivial part of the functioning of the overall system when implementing a closed-loop control system using a common communication system.
Earlier short range wireless networks pose a problem since delay deadlines are not used in packet consideration and regardless of these requirements, the packets are treated the same. For a closed loop control system, this presents a major challenge since actuators influencing the system are controlled by the sensor’s data. Data delays lead to negative reinforcement, hence instead of a process being kept within close limits, it runs away. (more…)

Analog Devices AD587KN 10V reference chip


SteelCity Electronics published an article about Analog Devices AD587KN 10V reference:

I recently got hold of an Analog Devices AD587KN high precision 10.000V reference chip.
This model of chip has an output value of 10.000V ± 5mV (that is, an output value of 9.995V to 10.005V) straight out of the factory. A voltage drift of 10ppm/°C at 25°C meaning that the output voltage will drift by 10μV for each 1°C the chip is exposed to. Additionally, the chip has a voltage trim input, so if you have access to a precision voltmeter, the chip’s output value can be adjusted even closer to 10.000V.
Alternatively, the chip’s output can be trimmed to a value of 10.24V. You may think that a value of 10.24V seems like a strangely familiar number. A value of 1024 is the decimal representation of 10bits, that is 2∧10 = 1024. Why would I want a voltage reference that outputs a value of 10.24V? Because it makes any ADC or DAC conversions much simpler.

Analog Devices AD587KN 10V reference chip  – [Link]

Turn with it with a minimum effort


Wiha Proturn® screwdrivers enable a comfortable work, even in case you need to gain a high torque.

As we know, the “power” (torque) we´re able to reach by a common screwdriver depends mainly from two factors – from a screwdriver handle size and design and – from our own strength :-). Strength of our hand can be changed only by hard training but a screwdriver intended to gain a maximu “power” is available immediately. The Proturn series from compant Wiha is one of suitable series for this purpose. Series Proturn features a robust two-component handle, with parts made of hard plastic and a soft rubber resulting in a very good grip. Quality chrome-plated and through hardened CrVMo steel guarantees long lifetime.Practical opening in a handle enables comfortable and well-arranged hanging on a wall of your workshop. They´re suitable for all works on electrical devices up to 1000V AC/ 1500VDC (VDE and GS approval). Each screwdriver is individually tested according to IEC60900:2004. Directly from our stock we´re able to supply to you price-advantageous set 470N K601 containing 5 Proturn 3K electric screwdrivers (2,5×75/ 4,0×100/ 5,5×125/ PH1x80/ PH2x100) and one classic voltage tester.

Any other tools from Wiha we´re able to supply to you upon request in a short leadtime and at favourable conditions.

Turn with it with a minimum effort – [Link]

3A Unipolar Stepper Motor Driver


This tiny Unipolar stepper motor driver has been designed around SLA7078MPR IC from Sanken, It is unipolar stepper Motor driver can handle current up to 3 Amps, micro-stepping up to 1/16 steps. On-board Jumpers to set the Micro-stepping, Preset (Potentiometer) to set the current.

The SLA7070MPR series motor driver ICs features unipolar drivers. The clock-in type input interface allows simplified control logic, and options for built-in sense current detection and load circuit short or open protection (patent pending) provide lower loss, and lower thermal resistance.

The built-in excitation distribution circuit (sequencer) allows motor control using only the CLOCK signal for simple operations (rotate/stop), with motor speed control by frequency input into CLOCK pin. This eliminates logic signal lines required for conventional phase-input methods, and reduces demand on heavily-used CPUs.

Unipolar stepper board is high efficient stepper driver for Unipolar stepper motor been design for various application like robotics, control routers, lathes, mills, PCB drillers and engravers.

3A Unipolar Stepper Motor Driver – [Link]


Arduino Digital Capacitance Meter


by braulio777 @ instructables.com

This project lets you measure capacitors in an alone range of measure from 0.000pF to 1000uF. That is, a 16×2 LCD Display will be displaying a sole scale from 0.000pF to 1000uF whose main components will be an Arduino Uno and a 16X2 LCD Display.

Arduino Digital Capacitance Meter – [Link]

Understanding bioelectricity


by Maurizio @ dev.emcelettronica.com:

Our body is built with biological tissue. The tissue that can generate or detect bioelectrical signals is called excitable tissue. Some examples of this tissue (and its cells) are: neurons and muscular tissue. Neurons are responsible of transmitting the excitatory bioelectrical signal to another neuron (forming nerves) or to a muscle tissue, gland or brain, while muscular cells are responsible of muscular contraction and distension. Some specialized cells generate bioelectric signals: optic receptors (eyes), muscular cells that transmit the feeling of pain, etc. Bioelectricity concerns the magnetic and electrical fields produced by organisms or cells.

Understanding bioelectricity – [Link]