Ytsirk analyzed the remote control protocol from a LED license plate frame using the USB IR Toy. Also check out part I and part II that introduce the hardware. We can’t wait for the next installment that covers reprogramming the marquee with a battery powered IR Toy, it sounds like there’s a lot of potential mischief fun to be had.

There have been multiple reports of dead MODE LEDs in Bus Pirate v3, preorder 2. The cause seems to be a dirty contact on the LED. Most can be repaired by reheating the joint, and possibly adding a bit more solder.

In response to this problem, Seeed Studio has changed LED suppliers. We also implemented a visual LED inspection step to the self-test in firmware v3.6 and later. If you have a dead LED and would like replacement parts, please contact us.

A note from Seeed follows.

Since some of previous MODE LED are reversed, we isolated manufacturing causes but regard the LEDs as defect supply. Either because of its soldering pad getting dirty or reliability issue. All future LEDs we are using are switched to a different supplier. If people demand replacement or spare parts, please help collect a list and we will send along. Sorry for the trouble brought!

Here’s a new project we’d like to develop openly, like the recent logic analyzer board . This rough sketch shows a 48 channel LED controller with an ethernet interface. Our primary goals are:

• 48 channels of 10bit PWM LED control
• Ethernet interface
• Up to 120mA of LEDs per channel

The networked LED controller would use the 24FJ64GA002-SO as the main microcontroller, and an ENC28J60 for the network connection. A 25AA02E48 EEPROM would hold settings and a unique MAC address so multiple boards can share the same network.

The LEDs would be driven by three TI TLC5940s, each with 16 channels of 10bit PWM. The current of the LEDs is set with a single resistor, ideally this would be done with a digital pot for easy network configuration. This chip is cascadable, so an expansion header would make it possible to stack extra TLC5940s on top of the base.

The overview continues below. We’re eager to hear your suggestions here, or in the forum.
This design will have a bootloader, but it will be brought to a serial header only. We’ll ask seeed to find a cheap USB->serial cable and make the header compatible with that.

Like the #twatch, we’d like to give the board a ‘default’ demo mode, probably an implementation of the internet-driven ‘daft punk table’.

Any thoughts, suggestions? There’s also a forum for this design.

Halloween is only a few days away. We’re getting into the spirit by building a remote control color changing pumpkin. Channel buttons 0-8 on the remote toggle the colors of the rainbow. Button 9 activates an ‘angry pumpkin’ mode that flashes a scary red strobe for a few seconds.

It uses a minimal PIC 18F2550 circuit that decodes the remote control signals and drives a ShiftBrite color changing LED module. The F2550 is a USB PIC with a USB bootloader, so it’s technically a USB upgradable pumpkin too.

Full sized schematic image [PNG]. A PIC 18F2550 microcontroller decodes RC5 infrared remote control signals, and sends instructions to a ShiftBrite color-changing LED module. We used a PIC development board with SMD parts, but you could also build this on a breadboard or perf-board with through-hole parts.

The IR receiver converts infrared light from the remote control into a signal that the PIC microcontroller can decode. The receiver is connected to PORTB pin 2 (RB2) of the PIC. RB2 has an external interrupt with edge select that we used to trigger the IR decoder. RB2 also has a Schmitt buffer that cleans the incoming signal and helps prevents false triggers. All PORTB pins on the 18F2550 have internal pull-up resistors if your receiver is an old type that doesn’t have it’s own pull-up.

The color changing LED is a ShiftBrite module from Macetech.com. It’s driven by three PIC pins and powered by a 5volt supply.

The PIC firmware is a simple timer and interrupt-based RC5 remote control decoder.  It bitbangs ShiftBrite color instructions based on the remote command codes received.

The firmware ignores the RC5 brand code and looks only at the command. It should understand any RC5 remote control. RC5 is a really common protocol, usually available as a Philips TV on universal remotes.

0. Off 1.Red 2.Orange 3.Yellow 4.Green 5.Blue 6.Indigo 7.Violet 8.White (all colors) 9.Angry pumpkin (~10 seconds)

The channel buttons 0-8 control the color. #9 plays a 10 second ‘angry pumpkin’  red strobe effect and returns to a solid color. There’s lots of room for more effects, fades, and other options.

Browse the source SVN, or download the source and compiled HEX [ZIP].

We tried to make the top of the pumpkin shake in angry mode using offset-weight rumble motors from a game control pad. It wasn’t violent enough to look good in a video, though it does make quite a racket. Next year we’ll try it again with a solenoid.