3D Printing from Thingiverse!

So you've got a 3D printer and want to get started printing right away without designing anything? Visit www.thingiverse.com. You can always find something useful or at least interesting to print. Check out some of my early prints on my modified MendelMax 3D printer.

My print of chopmeisters "Roundom Vase"

My print of  Landru's "Rocket Shot Glass"

Also, take a look and follow my thingiverse page (cobra18t on Thingiverse) to stay up to date on my "things" that I post.

Happy printing!


-Thomas

BOOMStick Audio Modules

The SnakeEyes V0.02 board has most everything I want but still needs some tweaking. I did not like the 0402 components, so I am going back to 0603. Additionally, I think people are interested in having exactly what they need and not much else in order to save costs. With that in mind, my next iteration of the audio board will actually be a small collection of breadboard-friendly modules:

BOOMStick:
Closest derivative to the V0.02 but only mono output. This will have a buffered SD Card, buffered PWM, improved 1W class D audio amplifier, headphone jack, and volume control.

BabyBOOMER:
Pared down version that scraps the headphone jack and SD card support. This can be paired with the BOOMStick for stereo output. Or, two BabyBOOMERS can be used with a SD-enabled microcontroller, such as the Fubarino SD, for an even more streamlined stereo output with 1W output per channel when using 8ohm speakers.

BabyBOOMER prototype

Speaker:
These will be small breadboard friendly speakers with current limiting resistors


Stay tuned for more development...


-Thomas

SnakeEyes Audio Boards

A few months ago, I started work on an audio board for Arduino and Chipkit microcontrollers. I wanted something that could play good quality sound effects and music with a small form factor.

SnakeEyes V0.01

My first attempt was a mash up of an Arduino Pro Mini and the same functional structure of the Adafruit Wave Shield. I wanted something that could play all by itself when given a few commands. The host processor would then be free from the low-level audio generation. Small speakers were to be soldered directly to the board in the space above the SD card. This was not a good design from a manufacturing standpoint and frankly, I am not a huge fan of Atmel microcontrollers. I abandoned the project for a while since I was discontent with the results with this board.

SnakeEyes V0.01 Audio Board (front and back)

SnakeEyes V0.02

As noted in some of my previous posts, I found Lutz Lisseck's SimpleSDAudio library for Arduino that used high speed PWM to generate audio from a streamlined SD library. I have a working port of the library to the Microchip-based PIC32 Chipkit processors. The library is very simple and requires very little hardware to get basic functionality. To get higher quality sound, however, more circuitry is necessary.

V0.02 of the SnakeEyes Audio board was born. This used a completely different form factor and used SimpleSDAudio type hardware rather than Wave Shield inspired hardware. It sports Stereo 16-bit 78.125kHz buffered PWM audio generation when using a Chipkit board. The host processor handles all audio generation. It has a headphone jack and thumb wheel volume control as well as two small speakers. There is also the option to use external speakers.

SnakeEyes V0.02 Audio Board

Check for the next post about future audio boards.


-Thomas

FubarinoSDt

Great news! I have completed a prototype of my edited FubarinoSD board, the FubarinoSDt.

FubarinoSDt Prototype

This prototype offers minor edits to FUBAR Labs' Fubarino SD 1.4. The most notable changes from a user perspective is that it has:

• 512k program memory, versus 256k
• 800mA rated current for the 3.3V regulator
• The card detect pin on the new SD card adapter is routed to A14, a change notification pin that can generate an interrupt on change.
• Blue LED on pin 21...you gotta love the blue.

Sparkfun's locking headers and slightly different parts were used for cost reasons, but the impact on the user should be minimal. 

EmbeddedMan, one of the creators of the FubarinoSD, provided the bootloader for the new 512k PIC32 and it seems to work just as expected.

I will post a video of it running my BasicSDAudio library soon.

-Thomas

Fubarino SD - New PIC32 Dev Board on the Block

Fubarino SD

For those that have not seen it yet, the Fubarino SD is a breadboard friendly, MPIDE (forked from Arduino IDE) programmable, PIC32-based development board from FUBAR Labs.

It is based on the PIC32MX440F256 which means that it runs 80MHz, has 256k Flash, and 32k RAM. There is a micro SD card socket on board connected to the PICs hardware SPI port. It also has USB OTG which means no FTDI serial interface and therefore faster serial communication. This direct USB interface is similar to the newest Arduino, Leonardo.

Fubarino SD avalaible at Seeed Studio Bazaar

With the great performance expected from this chip and the support that already exists for the board in MPIDE, I definitely plan on testing one or two out.

The SDt Version?

I have completed a new layout of the Fubarino SD to incorporate a few features that I want as well as support the packages for the parts I have available for build up of a couple boards. For lack of a better name, I am referring to it as the Fubarino SDt. Since I have just modified a few things, I thought I would toss my initial in there.

So what is different?

• Changed packages for crystal and diodes to match what I have available
• Used a different SD socket and brought the Card Detect out to a change notification pin
• Used a 800mA regulator for just a little more *umph*
• Used Sparkfun's locking headers so breadboarding does not require soldering
• Minor layout changes to adhere to my board fabricators design rules
• I also plan on using the PIC32MX440F512, which has 512k flash memory.

Time for some prototypes!


-Thomas

BasicSDAudio ChipKit Library

I have been working on a few Arduino and Chipkit projects that could use some decent audio generation. Many people have used Adafruit's Wave Shield in the past, but I dislike the idea of having to bit-bang the second SPI port, it requires additional hardware, and there was no simple way to port the library over to ChipKit.

SimpleSDAudio minimal setup

Enter Lutz Lisseck's SimpleSDAudio library for Arduino. It uses a stripped down SD card library and hardware PWM to output 8 or 16 bit audio in mono or stereo. I tried it out on my Arduino Pro Mini and was pleased with the results. Since it is interrupt driven, you are free to do other things in your sketch during audio playback, so long as you call the "worker" routine--which updates the audio buffer--often enough.

The library code is pretty straightforward so it was easy to go in an change ATMEGA specific code for the Arduino to PIC32 specific code for the ChipKit. I have an preliminary version working, so check it out:

The audio in the video is 8 bit stereo, sampled at 78.125kHz. Without using any more pins, the ChipKit will be capable of 10bit output at this sample rate, and 11bit output at 39.062kHz. The Arduino is only capable of 8 bit stereo when using only two PWM pins.

For more information about the SimpleSDAudio library for Arduino, visit:
http://www.hackerspace-ffm.de/wiki/index.php?title=SimpleSDAudio


-Thomas

Adventures at Home Depot

Home Depot is always fun, so many opportunities to remind Thomas why he shouldn't bring his wife.

I think HD got wise, though. Why else would they carry orchids for $9.99 and put them right at the entrance? Have you ever seen a mom promise her child a treat if they are on good behavior at the store? Yeah, it's like that.

First on the list, propane for those Summer barbecues. Next, dirt for the garden.

Last year, Thomas had a very cool, very space-station looking hydroponic setup in the back yard. The problem, though, was that instead of having to constantly monitor water volume, he had to constantly monitor water temperature, chemical and PH levels.

That plus the wind. A plant the has a constant water supply grows quickly, but the stems aren't so strong. After loosing much of the garden to previously mentioned issues, one day the pepper plant snapped in half. So did my guy's will power to continue hydroponic gardening in the desert.

It wasn't a complete loss, Thomas grew enough jalapenos and bell peppers to make a batch of hot sauce. We also had an abundance of mint and basil - it was a pesto and mojito Summer.

This year, back to dirt. Stinky dirt that smells like poop. We picked up a couple bags and also a soaker hose that is made of some kind of canvas-like material so that the water seeps through instead of squirting of out little holes. Clever.

Then, we head over to the PVC aisle, wifey following at a distance because she's looking at flowers and wants to stay away from the stinky poop dirt in the cart.

Thomas has a question, walks away to find someone in an orange apron. It takes us a while to track one down. I see a stack of orange bucket lids, and they look very much like frisbees. I pick one up. No, remember the orchid. Put it back down.

Finally, I see an orange apron in another aisle and smile at him. He says "Do you need help?" I lead him to my guy and say "I got one! I got one!" Good wifey, but this guy didn't know the answer. Should I fetch another one? No, it's okay.

I leave them and their PVC and stinky poop dirt to go sit down in the windows and doors department where there are tall chairs to sit on.

A few minutes later, Thomas is done and he heads toward the door, patting his leg and whistling for me to come. I gallop after him. Good wifey, happy with her pretty new orchid.