RK11-C indicator panel inlays?

David Bridgham dab at froghouse.org
Mon Dec 6 14:07:34 CST 2021

On 12/6/21 10:36 AM, Mike Katz via cctalk wrote:

> Each LED requires 24 bits of data.  That would be 3,456 bits.  The
> WS2812B has a 300uS low start indication and 1.25 uS per bit.  That
> would mean it would take. 4.62mS to update the all of the LEDs.

If I'd known about those when I designed my boards, I might well have
gone that way.  They're surprisingly inexpensive even.

Instead, I ended up using a 16-LED driver chip that basically looks like
a shift-register.  I clock in the 144 bits (just on-off, no fancy
tri-color LEDs I'm afraid), toggle the latch signal, and there it is. 
If you want to support more indicator panels, it's just a longer shift
register.  I then added RS422 driver chips for noise immunity and there
I was.


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