Posts filed under ‘BlipBox’

New year, new PCBs

Okay so it’s February already, but things are finally moving again with the project and a few new PCB’s are on order.

The previous design that we tried used a MIC5891 serial-input latched source driver. This seemed perfect on paper, but turned out not to work at all with 5v USB power because the IC drops too much voltage to drive the LEDs. Dang! And having at least the option to power by USB only is something we don’t want to sacrifice.

The new design by contrast uses discrete transistors to drive the LEDs, which are multiplexed by the microcontroller. This design can take a separate, higher input voltage, but also works fine with 5v. At least it does on the breadboard, we’ll have to wait and see how the PCB behaves!

Delivery is due in early March, news to follow shortly thereafter.

Advertisements

February 25, 2011 at 1:33 pm 2 comments

BlipBox Circuit Design Changes

Due to certain intermittent, but persistent problems with the last batch of PCB’s we’ve decided to make some design changes.

This means that BlipBoxes will not be available for sale for yet a bit more time, so apologies, again, to those of you waiting.

We don’t want to offer up a device that is not completely reliable, but rather take the time to fix the problem properly.

The good news is that we are already testing a new circuit which includes the MIC5891 source driver. This can drive the LED’s with up to 500mA, which is more than enough for our purposes. In fact, it should be more than enough even for a superbright blue LED version in the future.

Prototype PCB’s are currently on order, we expect to have them fully tested within the week. More news to follow.

March 25, 2010 at 7:03 am 2 comments

New Logo

Our good friend and talented designer Jim Otton has done a brand new BlipBox logo, which now adorns both our blog and website. He’s also done some other designs for us, more of which you will be seeing soon. We hope you enjoy.

blip stickers

Cheers Jim!

September 16, 2009 at 9:12 pm Leave a comment

Boxes Arrived

The new aluminium enclosures have arrived, custom milled and ready to be stuffed with electronic goodies.
This means we can now sell a number of ready made BlipBoxes, as soon as we’ve made them that is. Those on the mailing list will be informed of all the details.

Box of Boxes

Box of Boxes

September 13, 2009 at 9:26 pm Leave a comment

Processing

Someone recently suggested integrating the BlipBox with Processing. The Processing language is:

an open source programming language and environment for people who want to program images, animation, and interactions.

This was such an excellent idea that we simply had to do it. And now the beta version of the BlipBox Processing (or p5 if you prefer) library is ready!

Here’s an example of a very simple Processing sketch that talks two-ways with a BlipBox:

ProcessingBlipBox blipbox;
int x = 0;
int y = 0;
int value = 255;

void setup(){
  blipbox = new ProcessingBlipBox(this);
}

void draw(){
  blipbox.setLed(x, y, value);
  if(++x == 10){
    x = 0;
    if(++y == 8 )
      y = 0;
  }
  if(blipbox.isScreenPressed())
    value = blipbox.getX(0, 255);
    // scales X position to 0-255 range
  delay(20);
}

For this to work, the blipbox.jar library has to be added to the sketch using the PDE (Processing Development Environment).

What the sketch does is the following:
It iterates over all LEDs by column and row, setting them to an initial value of 255 (maximum luminosity).
If at any point the touch screen is pressed, then the value is changed to reflect the horizontal position of the touch.

The library code is currently in CVS and will be part of the first BlipBox public release, so that everyone can sketch with the ‘box!

Updated: here’s a silly little video to show y’all it’s for real:

September 13, 2009 at 6:56 pm Leave a comment

It Works!

Having battled with flicker on the new PCB for some time now I decided to build another board, to do some creative rewiring, and see what happens.

So guess what? The new board works just fine. Without modifications.

To my embarrassment I didn’t much consider that there could be some freak component or connection problem with the first board I soldered up. But that’s exactly what seems to be the case. One lives and one learns. Then one forgets.

The upshot of this all is that
1) I’ve rewritten, optimised and generally improved almost every part of the firmware trying to fix this problem.
2) I am reluctant to send out kits until I figure out what caused the flicker in the first place. Any ideas?

In the meantime I will build a couple of units and put up for sale. Enclosures shall be ordered, but won’t arrive for some 3-5 weeks. Watch this space.

And with that, a sincere thank you for continued support and patience!

August 5, 2009 at 1:05 am 3 comments

Firmware Troubles

I’m working hard on fixing some issues with the firmware which gives problems with the new PCBs.
To start with I just couldn’t get the LED’s to light at all. Eventually I made some progress using the most excellent TLC5940 library, though I couldn’t integrate it with my multiplexing code.
Some of the problems have been down to my lack of understanding of how the processor’s various registers work, in particular how timers are configured. Others have been plain stupid but no less frustrating, such as incompatibility between various versions of the arduino development kit (0011 works, 0013 flakes out over interrupts and on 0015 my code won’t compile!).
Oh well, it’s a learning process, and I now have a completely rewritten and much improved LED controller. Currently everything actually works, more or less, and with same the code running on both the previous (v4) and latest (v6) PCBs. But on v6 there is flicker… Noticable flicker.
I’m not sure if this is due to me changing the LED multiplexing pins. On v4 all five multiplexing pins were on the same port, in v6 I swapped some out for pins on a different port.
Whatever the reason I’m still working on fixing it. Hopefully v6 will turn out to be fully, flicker-free functional. Meanwhile here’s a pic of how nice it will look.

BlipBox By Night

BlipBox By Night

May 29, 2009 at 12:15 am 8 comments

Older Posts


Categories

Feeds