Here’s a summary of major developments over the last week. Free PCB Friday is coming up soon.
Coming up:
Android Thermostat, an open source DIY home thermostat project based on Android:
Android Thermostat is an open source thermostat project ideal for programmers and electronics hobbyists. As the name suggests the application runs on Android phone that is connected to some basic electronic components for controlling your home HVAC system.It costs around $140 to build and can be assembled in an afternoon.
It has several advantages over a traditional thermostat including the ability to easily create multiple schedules that are as simple or complex as you like, remote control access, monitoring of usage and easy updates over the internet. It’s API and open source nature means you can further customize the thermostat to perform additional functions.
Via Hacked Gadgets.
Check out the video after the break.
Kenneth Finnegan writes:
As a quick first test, I built a quick adapter board between the GPS engine’s 2×5 pin header to the standard FTDI serial cable, with a diode and 0.3F capacitor (Yes, not micro Farads, 0.3 actual Farads) to keep the SRAM from losing the current GPS almanac every time I power cycle it (which cuts the GPS lock time down from 12.5 minutes to 20-30 seconds). The 1pps output from the received is connected to the CTS line on the FTDI cable.
Configuring GPSd is ridiculously simple: Tell it which serial port you have your GPS receiver connected to, and it figures out baud rate, which pin you have 1pps connected to, etc. Then just point your NTP server at two special local host addresses where GPSd makes the time information available.
The FT2232H USB 2.0 Hi-Speed breakout board is back in stock at Seeed Studio. This is a breakout with a FT2232H high-speed dual-channel USB-to-serial chip that has two JTAG debug channels.
Juan of ssihla build this DIY electronic load. He writes:
The design is based on some of the various diy electronics loads out there (like the one from Dave Jones). The mosfet is a P45N03LT , most likely I took it from some of the PC power supply I’ve “recycled”. I’m using two 25k potentiometers, one for coarse adjustment and the other for fine adjustment (10 turn pots are kind of expensive…). The control voltage varies between 0 and 5 volts and is divided by two with a couple of 10k resistors. The op-amp is an OPA2336, It has rail to rail output so the load can sink roughly up to 2,5. The op amp is powered with a 7805.
Tom Cousins of DOAYEE made this DIY nixie tube clock:
Below is the schematic for the project, as you can see I’m using 6 IN12 nixie tubes, each with it’s own 74141 nixie tube driver. These drivers are great! They simply connect directly to the nixies and display whatever 4 bit binary number you give them (if you give them anything above 9 they blank the display – hence why I use the number 10 in my code to blank the nixies). Because they take in a simple 4 bit binary number, I can hook them directly up to some shift registers to drive them, in my case I used 3 74HC595 shift registers (available everywhere), because they can be “daisy chained” together, meaning in the code I only have to write one 24 bit binary number and it will display all 6 numbers on the nixies. Though in reality I split them up into pairs and write three 8 bit binary numbers.
Check out the video after the break. Continue reading “Nixie tube clock”
An update on Brian’s Pick and Place controller v3:
Following from the previous Pick and Place Controller V3 Part 1 post we have now built and installed the new control board for the pick and place machine.
While building and testing the board we found an issue with one of the pins on the main microcontroller needed to be connected to the USB ports input power so we used a small wire to add this to the board.
Here’s a cool Mini LED volume towers project by Ben Finio. He writes a complete step-by-step instructions here:
The inspiration for this project started when I saw a variety of awesome stereo LED towers on YouTube (also referred to as VU meters). Many of the videos showed the end result, and maybe a slideshow of the assembly process, but lacked complete build details or a circuit diagram. So, I set out to find out how they worked, and build my own “mini” desktop version that would go nicely with computer speakers, instead of a big living room stereo. This Instructable will give you complete directions to assemble the required circuit (even if you have no electronics experience – you can even do it without soldering), build two LED towers, and hook them up to an audio input so you can simultaneously drive them and listen to music.
Check out the video after the break. Continue reading “Mini LED volume towers (VU meters)”
A video on using Bus Pirate v4 to talk to a TI bq27510 Fuel Gauge by pitface123:
The Fuel Gauge is mounted on the Fuel Tank Booster Pack.
A Papilio Pro that is programmed as Logic Sniffer is used as the Logic Analyzer and protocol analyzer.
Nifty prototyping platform.
JaWi’s OpenLogic Sniffer as Logic Analyzer client..
Via Twitter. Thanks @JanLCumps!
You can get a Bus Pirate v4 for $40, including worldwide shipping.
At last years Defcon conference in Las Vegas, NV, hardware hackers Joe Grand, Mark ‘Smtty’ Smith, LosT, RenderMan and FirmWarez discussed their experiences in using various microcontrollers. Interesting stuff, particularly If you’re just getting started with electronics and are trying to navigate the sea of available microcontrollers, microprocessors, and modules.
Jared Sanson posted an update on his OLED watch. He writes:
Here’s a few features of my firmware:
- USB HID Communication (No PC drivers required!)
- Watch face for telling the time (Kind of required…)
- Date & Upcoming events
- Accelerometer reading
- RTOS Kernel debug info
And some features planned for the future:
- Bluetooth 4.0 (Still need to get the IC for it though)
- Magnetometer readings
- Smart alarm clock that wakes me up at the ideal time, by detecting my sleeping patterns through the accelerometer
- Auto screen on by rotating or shaking my wrist
Via Electronics Lab.
@0x2B2B tweeted, “Case for my OLS, laser cut at @RazorLAB. Design file in post 2byt, make your own!
Why the case? Well, being the fan of OSS/OSH (that’s; Open Source Hardware :) that I am, this was a nice, affordable entry into the market of Logic Analysers.
It’s always great having bare P.C.B.s because come on, they just look downright cool, but, this is a tool, there are likely to be a lot of wires around, and plenty of potential to short something out. Trust me, I have learned my lesson already.
Get a Logic Sniffer for $50, with free worldwide shipping.
An open source Arduino-based CNC machine from Brazil. Jeferson, the Protoptimus founder, writes:
It’s time for Brazil to show its strength in the maker movement”
My name is Jeferson, the Protoptimus founder. I’m on a Catarse.me campaing, the largest Brazilian crowdfunding website, and I need your help.
We yearn to be the first big manufacturer of low cost and ease-to-use CNC milling machine with Arduino, in our country.
Unfortunately, our campaign it’s mainly for residents in Brazil and is only in Portuguese.
Via Open Electronics.
Chris of simpleavr documented a TMS0803/5 Emulating calculator build:
As this project emulates the original TI DataMath and Sinclair Scientific calculators, it operates exactly the same as the original ones. The keyboard layouts are similar in both calculators. On the PCB, the dominant key legends (on top of each key) are for TI DataMath, while the smaller legends (top and slightly left of each key) are for Sinclair Scientific emulating.
I had select the MCU clock speed to be 8 Mhz, which appears to more or less matches the speed of the original calculators. I only observe the speed of the original calculators on youtube videos.
The emulating calculator starts / defaults as TI DataMath. If you want to start the calculator as a Sinclair Scientific, hold down key “7” while turning on power.
Via the comments.
Check out the video after the break.
Another update on Scasagrande’s project, GPIBUSB Adapter rev4:
After working closely with a few individuals it was discovered that some of the pre-existing GPIB software (such as KE5FX’s tools) has some hardcoded serial port settings, one of which being the use of hardware flow control. After getting builds of the software tools with these disabled, some buffer problems were found using the default settings, under Windows, without the flow control. Running the software with WINE on Linux did not produce these issues. With some small tweaks to either the software or to Windows USB settings would fix the issue but that’s not very intuitive. A better long term solution would be to wire up the hardware flow control lines in the next hardware revision for use in a future firmware update.
That’s what I’ve done with the revision 4 PCB. In addition, I grounded a few unused digital lines on the micro to be able to, starting with rev4+, check what the hardware revision is in software. I also added two LEDs to the FT230X to allow it to signal on TX and RX.
Chris Holden of NerdClub shares his tips on how he successfully program an ATMega128:
Finally got an ATMega128 chip coded and programmed successfully. The great news is it doesn’t require Arduino. The even better news is, we can use Oshonsoft to write the code! Yay.
In this video Pete Mills demonstrates his blueShift project, an OpenXC LED tachometer he is working on:
An Arduino, some addressable LED’s, a bluetooth module, code and a 3D printer come together to make blueShift – An OpenXC LED Tachometer. blueShift is so named for the Bluetooth protocol used for data communication, and the use of a tachometer to indicate when to shift your car. It may be amusing to note that the driver and passengers traveling in this car would observe Blueshift when peering thru the windscreen, provided their velocity was sufficient.
Ondrej Karas of DoItWireless writes:
This article describes temperature and humidity measurement with DHT11 sensor connected to TR module. Circuit diagram is very simple. You need only power supply for sensor and one wire for data line. This line has to be “pull-uped” – sensor has open colector output.
Another Instructables by Jan Henrik, a police light with a Attiny25/45/85. He writes:
Hello, in this project I want to show you how to build a multi functional Police Light with a Attiny25/45/85 .
It will have serval animations , which can be changed with a button on the circuit board, it has 2 channels, which can be controlled with PWM. That allows us to add serval animations or police light flashing sequences. The maximum rated current per channel is 500mA, that allowes us to control high power LED´s, LED stripes or old Light Bulbs!
Via the contact form.
We go through a lot of prototype PCBs, and end up with lots of extras that we’ll never use. Every Sunday we give away a few PCBs from one of our past or future projects, or a related prototype. Our PCBs are made through Seeed Studio’s Fusion board service. This week two random commenters will get a coupon code for the free PCB drawer tomorrow morning. Pick your own PCB. You get unlimited free PCBs now – finish one and we’ll send you another! Don’t forget there’s free PCBs three times every week:
