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Zoot
04-27-2006, 12:38 AM
I've got 2 mounted LEDs on the front of my project that won't get hooked up to pins. Could I hook one LED up to my serial I/O line and one to my I2C SDA or SCL line? Would I get any adverse effects on my data I/O? I was thinking of behavior along the lines of the green "act" LEDs on the PSC and the Ping, or like the disk access light on a desktop computer.

There is a circuit kind of like this in Robotics with the Boe-bot, p.48., for monitoring servo signal pulses. I was thinking a bigger resistor (1k) for a dim LED.

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When the going gets weird, the weird turn pro. -- HST

PJ Allen
04-27-2006, 12:53 AM
I think that the pulses will be so quick that you can/could not see them.

Zoot
04-27-2006, 01:03 AM
The I2C I'm not sure about, yeah. But I found the schematic of the LED act light for the PSC (attached below). I run my PSC at 38k and I see that light all the time....

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When the going gets weird, the weird turn pro. -- HST

PJ Allen
04-27-2006, 02:02 AM
Not to say there aren't options. You could use an op-amp, they have high ZIN, and use that to trigger a 555 (as a one-shot) which you could use as a"pulse-stretcher." This would indicate "activity".