App note: An explanation of LCD viewing angle


An application note from Hantronix, Inc. on LCD viewing angles and how it influences the selection of the right LCD for your application. Link here (PDF)

LCD displays have a limited viewing angle. They lose contrast and become hard to read at some viewing angles and they have more contrast and are easier to read at others. The size of the viewing angle is determined by several factors, primarily the type of LCD fluid and the duty cycle. Because the viewing angle tends to be smaller than most people would like, a bias is designed into the module at the time it is manufactured. This means the nominal viewing angle is offset from the perpendicular by some amount. Several versions of the LCD module are then offered with this bias set to different angles or positions to accommodate as many applications as possible. The term “bias angle” is often used erroneously with the term “viewing angle”.

App note: Designing with the EZ-USB FX3 Slave FIFO Interface


Designing with the EZ-USB FX3 Slave FIFO Interface application note (PDF!) from Cypress:

AN65974 describes the synchronous Slave FIFO interface of EZ-USB FX3. The hardware interface and configuration settings for the FLAGs are described in detail with examples. The application note includes references to GPIF™ II Designer to make the Slave FIFO interface easy to design with. Two complete design examples are provided to demonstrate how you can use the synchronous Slave FIFO to interface an FPGA to FX3.

App note: MMCM and PLL dynamic reconfiguration


Xilinx application note (PDF!) on MMCM and PLL dynamic reconfiguration:

This application note describes the information necessary to reconfigure the MMCM or PLL and provides a reference design that implements all of the algorithms covered. The PLL and MMCM share very similar functionality but are not identical. Due to some subtle functionality differences and the requirement for different settings, a separate PLL reference design is provided. To ensure correct operation, use the correct reference design for the clock management tile (CMT) being reconfigured.
Reconfiguration is performed through the DRP. The DRP provides access to the configuration bits that would normally only be initialized in the bitstream. This allows the user to dynamically change the MMCM or PLL clock outputs while the design is running. Frequency, phase, and duty cycle can all be changed dynamically. Fine-phase shifting is not allowed for the initial configuration or during reconfiguration.

An S/PDIF sound card using the PCM2906


Joesugar writes:

When S/PDIF became available in the Teensy Audio Library I thought this might be the solution to ground loop problems I’d been having when interfacing projects to my PC. However, I quickly realized I didn’t have any sound cards with an S/PDIF interface.
In the belief that I’d rather build than buy I decided to update one of my previous projects, a PCM2904 based sound card, to include an S/PDIF interface.

More info at Computer/Electronics Workbench site.

OpenDrop – Digital Microfludics Plattform


An open source digital microfludics platform from GaudiLabs, that is available on github:

OpenDrop is a new design for an open source digital microfludics platform for research purposes. The device uses recent electro-wetting technology to control small droplets of liquids. Potential applications are lab on a chip devices for automating processes of digital biology. How ever the present design should also open the technology to other field and allow experimentation to find new applications. Including the field of art, music, games and education.

More info at GaudiLabs project page.

Check out the video after the break.

PWM dimmer for LED lighting


Lukas Fassler has published a new build, a DIY PWM dimmer for LED lighting:

I have recently moved to a new apartment and was looking for a PWM dimmer to control some 12V LED strips. I thought that should be easy enough nowadays but it proved more difficult than I thought. All I found either didn’t meet my requirements, were uggly or expensive. So I decided to build my own, tailor-made to my needs.

Project info at Soldernerd site.

Quantifying cooling


Chris Palmer (a.k.a nophead) has designed and built this coolometer project to quantify the cooling effectiveness of various fan:

I was wondering about how I was going to calibrate the airflow reading but then realised that the flow rate is not actually what I am interested in. It is the cooling effect the airflow has, which is what I am directly measuring. The result is simply the extra power needed to maintain a target temperature and is a measure how fast the bulb filament is being cooled. So rather than an anemometer I decided to call it a coolometer. Unfortunately Futurama used that name first. Rather than displaying megafonzies mine displays milliwatts!

Project info at HydraRaptor blog.

Programmable CW Morse Keyer / beacon


Marko Pavlin has designed a Mini USB dongle with STM32F0xx , he writes:

Mini USB dongle with STM32F0xx is suitable many for simple, mini projects. I attached speaker to Timer14 PWM output (Pin PA6) and LED (or optocoupler connected to PTT) to GPIO pin PA0
The provided software is based on USB Virtual Com Port (VCP) device. The setup is done with command line interface using terminal from any PC. The setup is stored in the internal flash and PC is not required for normal operation. The mini beacon keyer can be used when powered with 5V.

Project info at Mare & Gal Electronics.

Inside the arm1v – the ALU control logic


Dave writes:

This is one of a number of posts on my work on reverse engineering the armv1 processor. The first in the series, and an index of the other articles can be found here.

My first post in this series described in some detail a one-bit slice of the ALU, and identified quite a number of control signals that feed all 32 bit slices which determine how the ALU operates. Now that I’ve reverse-engineered the overall instruction decoding and sequencing mechanism we now have enough context to make a start on reverse-engineering the circuitry that generates the ALU’s control signals. This turns out to be more complex than I first expected and a full understanding of what’s happening will probably have to wait until other parts of the processor have also been reverse-engineered.

More details at Dave’s Hacks blog.