Bring the Awesome

At long last (BatchPCB shipped them over two months ago), the 16...

Sun, 25 Oct 2009 18:09:28 +0000

At long last (BatchPCB shipped them over two months ago), the 16 x 16 boards have arrived. They were most likely a victim of the postal strikes here in the UK.

Big Chill

Tue, 11 Aug 2009 11:10:42 +0100

I dragged Ishani’s Rev2 to the Big Chill this past weekend. Initially, we were planning on making a run of the stripped-down Rev3 to hand out, but a stack of other committments got in the way.

In the process, I learned some valuable lessons:

Battery life “in the wild” will always be shorter than expected. We got between two and three hours out of it with a typical pattern. Field-replaceable batteries might be a sensible option.
Perceived brightness varies widely with ambient light (duh!). While having panel intensity embedded in the animation data is nice, some sort of brightness control on the device would be nice as well as useful for extending battery life.
Laptops are not particularly festi-friendly. Even my little EEEPC was a bother to tote around. Aside from swapping patterns from time to time, it was only used for recharging.
Finally, there was so much going on to hear and see I wasn’t hugely interested in playing with silly electronics!

It’s mounted in a picture frame. So.. yes. Yes it is.

Sun, 02 Aug 2009 16:22:58 +0100

It’s mounted in a picture frame. So.. yes. Yes it is.

It's alive!

Thu, 16 Jul 2009 10:47:59 +0100

Rev2 is up and running, blinking and blending away on Ishani’s desk.

After much cogitation, it would appear I swapped data in and data out to the MAX6960 while swapping pins in the firmware to match the new board layout. I can never remember from which perspective those are supposed to be interpreted.

As always, there are still some issues with Rev2:

When it is turned off but plugged in to USB the display still runs. It appears to be a case of power being pushed through the clamping diodes on the AVR. It’s either the USB interface (which is bus powered) or the charge indicator (which is foolishly connected directly to the bus power. Regardless of the cause, it means that when plugged in to USB it should either be switched on or have the display disabled in firmware.
The buttons are ridiculously small, so much so as to be completely unusable. Future revisions will replace with a single, larger button.
As mentioned before, the strap tabs are on the wrong way around and obscure the switches and USB connection.

Pushing forward with Rev3 (which should be renamed as it shares very little with the previous designs) in the meantime.

We are experiencing some delays getting Rev2 working. It passes...

Wed, 08 Jul 2009 15:39:47 +0100

We are experiencing some delays getting Rev2 working. It passes all of its self tests with the exception of the display. Communication between the two boards appears to be the same as with Rev1 but fails to produce an image.

Pleased to have my logic analyzer around. Beats the hell out of chicken guts or tea leaves for figuring out what’s gone wrong with inter-chip communication. There may be subtleties to timing that I have missed.

Photo

Thu, 25 Jun 2009 14:39:00 +0100

Mostly assembled. Waiting on the USB to serial IC.

Thu, 25 Jun 2009 14:39:00 +0100

Mostly assembled. Waiting on the USB to serial IC.

Some fresh circuit board pr0n.

Thu, 25 Jun 2009 14:37:00 +0100

Some fresh circuit board pr0n.

Photo

Thu, 25 Jun 2009 14:37:00 +0100

Rev2 boards are back...

Tue, 23 Jun 2009 16:05:00 +0100

…and lookin’ pretty sweet (will post pictures shortly). I put the tabs on the display board the wrong way around, so the USB connection and switches will be obscured by the strap. I think we’ll assemble two anyway, for fear of never getting anything done.

Still having trouble sourcing the MAX6960s for any reasonable price, which is a shame. I’ve not been able to produce quite the same display quality with Rev3’s ISR-driven approach. Specifically, balancing the red and green is proving very difficult.

Bank holiday weekends, the perfect time to get stuff done! Both...

Tue, 26 May 2009 11:11:00 +0100

Bank holiday weekends, the perfect time to get stuff done! Both fronts advanced quite significantly over the last three days; John will no doubt post an update in due course - the toolchain rewrite is going well, the fundamentals are all in and it’s all so much neater. Decided to give VS 2010 and .NET 4.0 a try, so far so good..

While John diligently revs the hardware, I have decided to...

Fri, 22 May 2009 19:25:00 +0100

While John diligently revs the hardware, I have decided to refactor the current Badge toolchain into something more elegant and maintainable. The current version is messy and the scripting API is pretty wonky. Have already rewritten most of the Frame class (which defines the pattern on the matrix for a single step of the animation) - building better systems for managing LED state, pushing frame data around the tool more efficiently, responding to changes in a Model-View pattern… much happier with it already!

Holy Macaroni

Tue, 19 May 2009 14:34:00 +0100

It’s been a busy year in the 64-pixel space. This enterprising lad is getting dangerously close to The Awesome. He must be ~~stopped~~ congratulated and given a slice of cake.

That said, he and this guy have put together some pretty nice minimal board designs that might ~~need to be plagiarized~~ provide inspiration for the consumer version. I reckon we could knock the parts cost down below ten bucks if we were willing to take this sort of route and give up on rechargeable batteries and the USB connection.

Rev2 boards are on their way to be fab’d. Much cleaner...

Mon, 18 May 2009 10:34:00 +0100

Rev2 boards are on their way to be fab’d.

Much cleaner main board design with lots of test points on the back for programming and testing with a pin jig.
Added missing pull-up resistors on the i2c memory bus.
Removed the fancy (and expensive) navigation switch in favor of two bog-standard SMD pushbuttons.
Added fancy tabs to the display board for a mounting strap of some sort. The fab house doesn’t do inside routing, so I stacked a bunch of drill hits to make the slot. Hope it works out..

10 minutes with Rev1 and some new Badge tool code…

Thu, 14 May 2009 22:43:00 +0100

10 minutes with Rev1 and some new Badge tool code…

A quick snap of the Rev1 prototype; Although it’s already...

Thu, 14 May 2009 22:41:00 +0100

A quick snap of the Rev1 prototype; Although it’s already pretty compact, John estimates we can shave a 1/3 off the height on the next revision.

Photo

Thu, 14 May 2009 22:30:00 +0100

Ignition! Captured on a Lumix FX150, here’s John’s...

Tue, 12 May 2009 16:01:00 +0100

Ignition! Captured on a Lumix FX150, here’s John’s salvaged Rev1 prototype running a few of the default demo sequences…

Stuff to notice:

+ per-frame controllable brightness, for pulse-y epileptic fun

+ text scrolling - super easy to make, just type words into the Badge tool and it does all the work

+ tasty polar plasma! (3rd shot)

Battery Operation

Tue, 12 May 2009 10:14:00 +0100

Things got really hot when I soldered in the battery this morning. Turns out I’d made a silly mistake wiring the charging circuitry. If the battery hadn’t had it’s own overcurrent protection, we might have had a pretty nasty fire. Anyway, one pin-lift and the device is now free-standing.

In other LED news, check out these fancy LED invitations.

The Awesome, Rev 1

Mon, 11 May 2009 15:48:00 +0100

It turns out the Rev 1 boards were salvageable after all. Some clever bending of leads, wedging-in of tiny resistors and a couple of green (I use yellow) wire fixes and we’re up and running.