ShiftBrite is a simple device I am designing and producing. It allows easy control of a bright RGB LED. The interface is a straightforward clocked serial data line and a latch input. All signals are buffered and passed through for good performance over long cables and daisy chaining many devices. Many ShiftBrite devices can be controlled from any type of controller that supports clocked serial data output, which is practically all microcontrollers and even PC parallel port or FTDI bitbang adapters.
10 thoughts on “RGB LED controller”
Comments are closed.
ADVERTISEMENT
Join Make: Community Today
Isnt the blinkm easier?
Whoa, this wasn’t quite ready for primetime yet. Anyway, I’ll have a bunch of these running at the Maker Faire Bay Area 2008 this May 3rd and 4th. Well, assuming my Chinese assembler is able to meet the deadline.
AF: BlinkM and ShiftBrite may look similar, but they work differently and are intended for different markets, though some overlap exists. The ShiftBrite was actually in the design stage before the BlinkM was released. If you’re writing code from scratch, ShiftBrite is actually easier to use because you simply pulse one line and shift the next bit of data on the other. When you’ve sent the whole command, pulse the latch line. This means there is no need to implement the full I2C protocol. ShiftBrites are also daisy chained, the identity of an LED is defined by its location on the string, rather than having to pre-program every LED like the BlinkM. However, this means you must send out the status of every LED even if you only want to change one; with the BlinkM you can speak to one LED on the I2C bus and leave the other alone.
The ShiftBrite is intended for users who want to control several RGB LEDs in 30-bit color, and don’t need the scripting and auto-sequencing of the BlinkM standalone modes. It uses a chip that needs no programming and does current regulation, dot correction, thermal auto-shutoff and restore, and buffered outputs for longer cable runs between LEDs. Since the ShiftBrite uses inexpensive parts, based on current quoting I should be able to start these near $5 in single quantities with discounts possible for multiples.
Anyway the launch is supposed to happen around Maker Faire, so see you then….
Yup, ShiftBrite is great for when you want to control a large number of RGB LEDs and want to do things like video with them. The chip in ShiftBrite is really cool and I’m so glad you’re making a board for it, since those QFN packages are hard to work with.
BlinkM is more for when you have limited processing on the controller side and want to push off some of the RGB color changing to the LEDs themselves, since BlinkMs can run little “programs” of color changes. Due to the limitations of I2C (127 address range), it’s not really made for large arrays.
BlinkM & ThingM will be at Maker Faire too. Garrett, I hope we can meet up and say “hi”!
how many addresses can be set?
Please let me know if you’re looking for a author for your blog.
You have some really great articles and I believe I would be a good asset.
If you ever want to take some of the load off, I’d absolutely love to write some content for your blog
in exchange for a link back to mine. Please shoot me
an e-mail if interested. Kudos!