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8 years, 11 months ago.
LED brightness
This should be a "Start a discussion" but that form seems to be broken (the input fields are totally missing).
Anyway, about the FRDM-K22F. I really like this board. It has a nice form factor, nice mounting hole positions, lots of pins and peripherals. About the only bad thing you can say about it is that the chip is a bit archaic (e.g. the flextimers are just annoying to use). Fortunately the mBed API protects us from that usually.
Which means the worst thing about it is the RGB LED. It is brighter than the sun itself! I suspect it is even brighter than it should be because the blue LED has died in mine.
If you make another revision of this board I recommend you reduce the brightness to at most half its current level.
Question relating to:
Hi Tim, Have you tried PWM to control the brightness? see pwmout.h It's much more efficient than using a larger resistor to limit current. Kind Regards
posted by Martin Simpson 03 Jun 2015Ha that's ... why didn't I think of that? Thanks!
posted by Tim H 04 Jun 2015Actually, the blue LED hadn't died - I just didn't realise that the LEDs are connected to D3, D9 and D13 and I was using those pins for other things. Seems like a weird decision to connect them to standard arduino pins (except D13; that makes sense).
posted by Tim H 08 Jun 2015