Bit-bang FTDI USB-to-serial converters to drive SPI devices

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Scott W Harden writes , “The FT232 USB-to-serial converter is one of the most commonly-used methods of adding USB functionality to small projects, but recently I found that these chips are capable of sending more than just serial signals. With some creative programming, individual output pins can be big-banged to emulate a clock, data, and chip select line to control SPI devices.
This post shares some of the techniques I use to bit-bang SPI with FTDI devices, and some of perks (and quirks) of using FTDI chips to bit-bang data from a USB port. ”

See the full post on Scott Harden’s blog .

Check out the video after the break

 

An easy way to mount DS18B20 temperature sensors

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Matt wrote an article describing a technique he used to mount DS18B20 temperature sensors:

One of the biggest advantage of these sensors over I2C sensors, is that you can mount them almost anywhere. That having been said, I’ve never quite managed to come up with an elegant solution, particularly when attaching to a heatsink (for cooling applications)

More details at Matt’s Tech Pages.

 

 

Using DC motors to power computers

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Electric generator experiment from HomoFaciens:

The generators I am using are in fact geared DC motors, left over from a project with my sponsor RS Components. The modern abacuses being powered during my experiments are a Raspberry Pi Model, a SIMATIC IOT2020 and an Arduino Uno. A 2×16 characters LCD is used to display results. Two geared DC motors are on my board with the test setup

More info at HomoFaciens.de.

Check out the video after the break.

StyloCard

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Stylophone business card project from mitxela.com

Printed Circuit Boards as a business card are a great gimmick. I’d seen ones with USB ports etched into them, which enumerate as a keyboard and then type a person’s name or load up their website. It’s just about possible to build them cheap enough to hand out as a business card, at least if you’re picky about who you give them to.
A couple of years ago I took a stab at making one for myself, but I didn’t want it to be pointless. I wanted it to do something useful! Or at least entertain someone for longer than a few seconds. I can’t remember quite how I got the idea of making a MIDI-stylophone, but the idea was perfect.

More info at mitxela.com.

Check out the video after the break.

Troubleshooting tips: Failed debugging with GDB

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Erich Styger writes:

Three years ago I published “Debugging Failure: Check List and Hints” and unfortunately this article is one of the most popular ones: obviously debugging problems are very common. Debugging with GDB works usually fine, but if things are failing, then it can be hard to find the cause for it. Recently I have been asked to check some failures, so here are two more hints about what could go wrong…

More details at MCU on Eclipse blog.

 

Yield function, printable class and mapping arrays: Useful but unknown features from Arduino core

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Yahya Tawil over at Atadiat wrote a new tip for Arduino developers about three hidden and useful features in Arduino core:

Arduino core, the source code of Arduino API functions and classes, has three useful features that can be used effectively. As the Arduino core documentation doesn’t mention them (at least until the time of publishing this micro-blog), these features are not well-known for arduino developers. Let’s discuss each feature of them one by one.

More details at Atadiat blog.

Via the contact form.

 

Common emitter amplifier design tips & shortcuts

Tips & tricks for the common emitter amplifier design by Alan Wolke (aka W2AEW)

This video provides some basic design tips and shortcuts for the Common Emitter, Class A, Amplifier. The considerations for selection of the DC Bias point are presented, as well as some tips on how to set/compute the gain for both degenerated and high-gain configurations.

Pimp your PCB businesscard full color

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Here is a nice PCB businesscard @ smdprutser.nl

As a good electronic hobbiest tradition I started to design a businesscard from PCB material. Downside of all the businesscards (and PCBs in general) is the limited number of colors you can use: FR4, soldermask (with or without copper behind it), silkscreen or bare copper. Since the soldermask is fixed for both sides that was an extra limiting factor.
An out of the box solution I found was decal slide paper. This is a printable plastic film that is used to decorate ceramics or glass. There are clear and white versions and they can be found in most hobby stores. They are easily printed on by an inktjet or laser printer and have thus an infinite range of colors. For this experiment I bought clear film and designed the PCB with black soldermask (needed that color for the front side) and white silkscreen.

More details here.

Using Python to store data from many BLE devices

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Erich Styger has written an article describing a technique he used to collect and store data from several BLE devices with Raspberry Pi and Python scripting:

BLE (Bluetooth Low Energy) sensor devices like the Hexiwear are great, but they cannot store a large amount of data. For a research project I have to collect data from many BLE devices for later processing. What I’m using is a Python script running on the Raspberry Pi which collects the data and stores it on a file

More details at mcuoneclipse.com.