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Unread 18-01-2008, 21:05
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Dr. Skloss
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Re: Problem with 2008 gear tooth sensor

Quote:
Originally Posted by Larry R View Post

This brings up my final question. From looking at the software, it seemed to me that due to the narrow uS spikes that the KOP gear tooth sensor outputs, you employed an interrupt-driven approach: " In the RC we used interrupts 2 and 3 (on RC DIO pins 1 and 2). Every time the gear tooth stimulates a low-to-high transition on the signal pin, an interrupt is thrown. "

I note that you referred to a low to high transition generating an interrupt. However the Honeywell units make a high to low. I am assuming the interrupt is edge sensitive and not level sensitive. Am I right about this?

Thanks a million for all your help!
Cheers, Larry
The RC triggers the interrupt on the edge type, rising or falling. Since the sensor gives a repeating square pulse as the gear teeth fly by, you get both types and simply have to choose one. Glad you got it working. We calculated a resolution of 0.07 inches of robot travel per tick in our setup.
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